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/highuid.h>
31 #include <linux/pagemap.h>
32 #include <linux/quotaops.h>
33 #include <linux/string.h>
34 #include <linux/buffer_head.h>
35 #include <linux/writeback.h>
36 #include <linux/mpage.h>
37 #include <linux/uio.h>
38 #include <linux/bio.h>
39 #include <linux/fiemap.h>
43 static int ext3_writepage_trans_blocks(struct inode
*inode
);
46 * Test whether an inode is a fast symlink.
48 static int ext3_inode_is_fast_symlink(struct inode
*inode
)
50 int ea_blocks
= EXT3_I(inode
)->i_file_acl
?
51 (inode
->i_sb
->s_blocksize
>> 9) : 0;
53 return (S_ISLNK(inode
->i_mode
) && inode
->i_blocks
- ea_blocks
== 0);
57 * The ext3 forget function must perform a revoke if we are freeing data
58 * which has been journaled. Metadata (eg. indirect blocks) must be
59 * revoked in all cases.
61 * "bh" may be NULL: a metadata block may have been freed from memory
62 * but there may still be a record of it in the journal, and that record
63 * still needs to be revoked.
65 int ext3_forget(handle_t
*handle
, int is_metadata
, struct inode
*inode
,
66 struct buffer_head
*bh
, ext3_fsblk_t blocknr
)
72 BUFFER_TRACE(bh
, "enter");
74 jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
76 bh
, is_metadata
, inode
->i_mode
,
77 test_opt(inode
->i_sb
, DATA_FLAGS
));
79 /* Never use the revoke function if we are doing full data
80 * journaling: there is no need to, and a V1 superblock won't
81 * support it. Otherwise, only skip the revoke on un-journaled
84 if (test_opt(inode
->i_sb
, DATA_FLAGS
) == EXT3_MOUNT_JOURNAL_DATA
||
85 (!is_metadata
&& !ext3_should_journal_data(inode
))) {
87 BUFFER_TRACE(bh
, "call journal_forget");
88 return ext3_journal_forget(handle
, bh
);
94 * data!=journal && (is_metadata || should_journal_data(inode))
96 BUFFER_TRACE(bh
, "call ext3_journal_revoke");
97 err
= ext3_journal_revoke(handle
, blocknr
, bh
);
99 ext3_abort(inode
->i_sb
, __func__
,
100 "error %d when attempting revoke", err
);
101 BUFFER_TRACE(bh
, "exit");
106 * Work out how many blocks we need to proceed with the next chunk of a
107 * truncate transaction.
109 static unsigned long blocks_for_truncate(struct inode
*inode
)
111 unsigned long needed
;
113 needed
= inode
->i_blocks
>> (inode
->i_sb
->s_blocksize_bits
- 9);
115 /* Give ourselves just enough room to cope with inodes in which
116 * i_blocks is corrupt: we've seen disk corruptions in the past
117 * which resulted in random data in an inode which looked enough
118 * like a regular file for ext3 to try to delete it. Things
119 * will go a bit crazy if that happens, but at least we should
120 * try not to panic the whole kernel. */
124 /* But we need to bound the transaction so we don't overflow the
126 if (needed
> EXT3_MAX_TRANS_DATA
)
127 needed
= EXT3_MAX_TRANS_DATA
;
129 return EXT3_DATA_TRANS_BLOCKS(inode
->i_sb
) + needed
;
133 * Truncate transactions can be complex and absolutely huge. So we need to
134 * be able to restart the transaction at a conventient checkpoint to make
135 * sure we don't overflow the journal.
137 * start_transaction gets us a new handle for a truncate transaction,
138 * and extend_transaction tries to extend the existing one a bit. If
139 * extend fails, we need to propagate the failure up and restart the
140 * transaction in the top-level truncate loop. --sct
142 static handle_t
*start_transaction(struct inode
*inode
)
146 result
= ext3_journal_start(inode
, blocks_for_truncate(inode
));
150 ext3_std_error(inode
->i_sb
, PTR_ERR(result
));
155 * Try to extend this transaction for the purposes of truncation.
157 * Returns 0 if we managed to create more room. If we can't create more
158 * room, and the transaction must be restarted we return 1.
160 static int try_to_extend_transaction(handle_t
*handle
, struct inode
*inode
)
162 if (handle
->h_buffer_credits
> EXT3_RESERVE_TRANS_BLOCKS
)
164 if (!ext3_journal_extend(handle
, blocks_for_truncate(inode
)))
170 * Restart the transaction associated with *handle. This does a commit,
171 * so before we call here everything must be consistently dirtied against
174 static int ext3_journal_test_restart(handle_t
*handle
, struct inode
*inode
)
176 jbd_debug(2, "restarting handle %p\n", handle
);
177 return ext3_journal_restart(handle
, blocks_for_truncate(inode
));
181 * Called at the last iput() if i_nlink is zero.
183 void ext3_delete_inode (struct inode
* inode
)
187 truncate_inode_pages(&inode
->i_data
, 0);
189 if (is_bad_inode(inode
))
192 handle
= start_transaction(inode
);
193 if (IS_ERR(handle
)) {
195 * If we're going to skip the normal cleanup, we still need to
196 * make sure that the in-core orphan linked list is properly
199 ext3_orphan_del(NULL
, inode
);
207 ext3_truncate(inode
);
209 * Kill off the orphan record which ext3_truncate created.
210 * AKPM: I think this can be inside the above `if'.
211 * Note that ext3_orphan_del() has to be able to cope with the
212 * deletion of a non-existent orphan - this is because we don't
213 * know if ext3_truncate() actually created an orphan record.
214 * (Well, we could do this if we need to, but heck - it works)
216 ext3_orphan_del(handle
, inode
);
217 EXT3_I(inode
)->i_dtime
= get_seconds();
220 * One subtle ordering requirement: if anything has gone wrong
221 * (transaction abort, IO errors, whatever), then we can still
222 * do these next steps (the fs will already have been marked as
223 * having errors), but we can't free the inode if the mark_dirty
226 if (ext3_mark_inode_dirty(handle
, inode
))
227 /* If that failed, just do the required in-core inode clear. */
230 ext3_free_inode(handle
, inode
);
231 ext3_journal_stop(handle
);
234 clear_inode(inode
); /* We must guarantee clearing of inode... */
240 struct buffer_head
*bh
;
243 static inline void add_chain(Indirect
*p
, struct buffer_head
*bh
, __le32
*v
)
245 p
->key
= *(p
->p
= v
);
249 static int verify_chain(Indirect
*from
, Indirect
*to
)
251 while (from
<= to
&& from
->key
== *from
->p
)
257 * ext3_block_to_path - parse the block number into array of offsets
258 * @inode: inode in question (we are only interested in its superblock)
259 * @i_block: block number to be parsed
260 * @offsets: array to store the offsets in
261 * @boundary: set this non-zero if the referred-to block is likely to be
262 * followed (on disk) by an indirect block.
264 * To store the locations of file's data ext3 uses a data structure common
265 * for UNIX filesystems - tree of pointers anchored in the inode, with
266 * data blocks at leaves and indirect blocks in intermediate nodes.
267 * This function translates the block number into path in that tree -
268 * return value is the path length and @offsets[n] is the offset of
269 * pointer to (n+1)th node in the nth one. If @block is out of range
270 * (negative or too large) warning is printed and zero returned.
272 * Note: function doesn't find node addresses, so no IO is needed. All
273 * we need to know is the capacity of indirect blocks (taken from the
278 * Portability note: the last comparison (check that we fit into triple
279 * indirect block) is spelled differently, because otherwise on an
280 * architecture with 32-bit longs and 8Kb pages we might get into trouble
281 * if our filesystem had 8Kb blocks. We might use long long, but that would
282 * kill us on x86. Oh, well, at least the sign propagation does not matter -
283 * i_block would have to be negative in the very beginning, so we would not
287 static int ext3_block_to_path(struct inode
*inode
,
288 long i_block
, int offsets
[4], int *boundary
)
290 int ptrs
= EXT3_ADDR_PER_BLOCK(inode
->i_sb
);
291 int ptrs_bits
= EXT3_ADDR_PER_BLOCK_BITS(inode
->i_sb
);
292 const long direct_blocks
= EXT3_NDIR_BLOCKS
,
293 indirect_blocks
= ptrs
,
294 double_blocks
= (1 << (ptrs_bits
* 2));
299 ext3_warning (inode
->i_sb
, "ext3_block_to_path", "block < 0");
300 } else if (i_block
< direct_blocks
) {
301 offsets
[n
++] = i_block
;
302 final
= direct_blocks
;
303 } else if ( (i_block
-= direct_blocks
) < indirect_blocks
) {
304 offsets
[n
++] = EXT3_IND_BLOCK
;
305 offsets
[n
++] = i_block
;
307 } else if ((i_block
-= indirect_blocks
) < double_blocks
) {
308 offsets
[n
++] = EXT3_DIND_BLOCK
;
309 offsets
[n
++] = i_block
>> ptrs_bits
;
310 offsets
[n
++] = i_block
& (ptrs
- 1);
312 } else if (((i_block
-= double_blocks
) >> (ptrs_bits
* 2)) < ptrs
) {
313 offsets
[n
++] = EXT3_TIND_BLOCK
;
314 offsets
[n
++] = i_block
>> (ptrs_bits
* 2);
315 offsets
[n
++] = (i_block
>> ptrs_bits
) & (ptrs
- 1);
316 offsets
[n
++] = i_block
& (ptrs
- 1);
319 ext3_warning(inode
->i_sb
, "ext3_block_to_path", "block > big");
322 *boundary
= final
- 1 - (i_block
& (ptrs
- 1));
327 * ext3_get_branch - read the chain of indirect blocks leading to data
328 * @inode: inode in question
329 * @depth: depth of the chain (1 - direct pointer, etc.)
330 * @offsets: offsets of pointers in inode/indirect blocks
331 * @chain: place to store the result
332 * @err: here we store the error value
334 * Function fills the array of triples <key, p, bh> and returns %NULL
335 * if everything went OK or the pointer to the last filled triple
336 * (incomplete one) otherwise. Upon the return chain[i].key contains
337 * the number of (i+1)-th block in the chain (as it is stored in memory,
338 * i.e. little-endian 32-bit), chain[i].p contains the address of that
339 * number (it points into struct inode for i==0 and into the bh->b_data
340 * for i>0) and chain[i].bh points to the buffer_head of i-th indirect
341 * block for i>0 and NULL for i==0. In other words, it holds the block
342 * numbers of the chain, addresses they were taken from (and where we can
343 * verify that chain did not change) and buffer_heads hosting these
346 * Function stops when it stumbles upon zero pointer (absent block)
347 * (pointer to last triple returned, *@err == 0)
348 * or when it gets an IO error reading an indirect block
349 * (ditto, *@err == -EIO)
350 * or when it notices that chain had been changed while it was reading
351 * (ditto, *@err == -EAGAIN)
352 * or when it reads all @depth-1 indirect blocks successfully and finds
353 * the whole chain, all way to the data (returns %NULL, *err == 0).
355 static Indirect
*ext3_get_branch(struct inode
*inode
, int depth
, int *offsets
,
356 Indirect chain
[4], int *err
)
358 struct super_block
*sb
= inode
->i_sb
;
360 struct buffer_head
*bh
;
363 /* i_data is not going away, no lock needed */
364 add_chain (chain
, NULL
, EXT3_I(inode
)->i_data
+ *offsets
);
368 bh
= sb_bread(sb
, le32_to_cpu(p
->key
));
371 /* Reader: pointers */
372 if (!verify_chain(chain
, p
))
374 add_chain(++p
, bh
, (__le32
*)bh
->b_data
+ *++offsets
);
392 * ext3_find_near - find a place for allocation with sufficient locality
394 * @ind: descriptor of indirect block.
396 * This function returns the preferred place for block allocation.
397 * It is used when heuristic for sequential allocation fails.
399 * + if there is a block to the left of our position - allocate near it.
400 * + if pointer will live in indirect block - allocate near that block.
401 * + if pointer will live in inode - allocate in the same
404 * In the latter case we colour the starting block by the callers PID to
405 * prevent it from clashing with concurrent allocations for a different inode
406 * in the same block group. The PID is used here so that functionally related
407 * files will be close-by on-disk.
409 * Caller must make sure that @ind is valid and will stay that way.
411 static ext3_fsblk_t
ext3_find_near(struct inode
*inode
, Indirect
*ind
)
413 struct ext3_inode_info
*ei
= EXT3_I(inode
);
414 __le32
*start
= ind
->bh
? (__le32
*) ind
->bh
->b_data
: ei
->i_data
;
416 ext3_fsblk_t bg_start
;
417 ext3_grpblk_t colour
;
419 /* Try to find previous block */
420 for (p
= ind
->p
- 1; p
>= start
; p
--) {
422 return le32_to_cpu(*p
);
425 /* No such thing, so let's try location of indirect block */
427 return ind
->bh
->b_blocknr
;
430 * It is going to be referred to from the inode itself? OK, just put it
431 * into the same cylinder group then.
433 bg_start
= ext3_group_first_block_no(inode
->i_sb
, ei
->i_block_group
);
434 colour
= (current
->pid
% 16) *
435 (EXT3_BLOCKS_PER_GROUP(inode
->i_sb
) / 16);
436 return bg_start
+ colour
;
440 * ext3_find_goal - find a preferred place for allocation.
442 * @block: block we want
443 * @partial: pointer to the last triple within a chain
445 * Normally this function find the preferred place for block allocation,
449 static ext3_fsblk_t
ext3_find_goal(struct inode
*inode
, long block
,
452 struct ext3_block_alloc_info
*block_i
;
454 block_i
= EXT3_I(inode
)->i_block_alloc_info
;
457 * try the heuristic for sequential allocation,
458 * failing that at least try to get decent locality.
460 if (block_i
&& (block
== block_i
->last_alloc_logical_block
+ 1)
461 && (block_i
->last_alloc_physical_block
!= 0)) {
462 return block_i
->last_alloc_physical_block
+ 1;
465 return ext3_find_near(inode
, partial
);
469 * ext3_blks_to_allocate: Look up the block map and count the number
470 * of direct blocks need to be allocated for the given branch.
472 * @branch: chain of indirect blocks
473 * @k: number of blocks need for indirect blocks
474 * @blks: number of data blocks to be mapped.
475 * @blocks_to_boundary: the offset in the indirect block
477 * return the total number of blocks to be allocate, including the
478 * direct and indirect blocks.
480 static int ext3_blks_to_allocate(Indirect
*branch
, int k
, unsigned long blks
,
481 int blocks_to_boundary
)
483 unsigned long count
= 0;
486 * Simple case, [t,d]Indirect block(s) has not allocated yet
487 * then it's clear blocks on that path have not allocated
490 /* right now we don't handle cross boundary allocation */
491 if (blks
< blocks_to_boundary
+ 1)
494 count
+= blocks_to_boundary
+ 1;
499 while (count
< blks
&& count
<= blocks_to_boundary
&&
500 le32_to_cpu(*(branch
[0].p
+ count
)) == 0) {
507 * ext3_alloc_blocks: multiple allocate blocks needed for a branch
508 * @indirect_blks: the number of blocks need to allocate for indirect
511 * @new_blocks: on return it will store the new block numbers for
512 * the indirect blocks(if needed) and the first direct block,
513 * @blks: on return it will store the total number of allocated
516 static int ext3_alloc_blocks(handle_t
*handle
, struct inode
*inode
,
517 ext3_fsblk_t goal
, int indirect_blks
, int blks
,
518 ext3_fsblk_t new_blocks
[4], int *err
)
521 unsigned long count
= 0;
523 ext3_fsblk_t current_block
= 0;
527 * Here we try to allocate the requested multiple blocks at once,
528 * on a best-effort basis.
529 * To build a branch, we should allocate blocks for
530 * the indirect blocks(if not allocated yet), and at least
531 * the first direct block of this branch. That's the
532 * minimum number of blocks need to allocate(required)
534 target
= blks
+ indirect_blks
;
538 /* allocating blocks for indirect blocks and direct blocks */
539 current_block
= ext3_new_blocks(handle
,inode
,goal
,&count
,err
);
544 /* allocate blocks for indirect blocks */
545 while (index
< indirect_blks
&& count
) {
546 new_blocks
[index
++] = current_block
++;
554 /* save the new block number for the first direct block */
555 new_blocks
[index
] = current_block
;
557 /* total number of blocks allocated for direct blocks */
562 for (i
= 0; i
<index
; i
++)
563 ext3_free_blocks(handle
, inode
, new_blocks
[i
], 1);
568 * ext3_alloc_branch - allocate and set up a chain of blocks.
570 * @indirect_blks: number of allocated indirect blocks
571 * @blks: number of allocated direct blocks
572 * @offsets: offsets (in the blocks) to store the pointers to next.
573 * @branch: place to store the chain in.
575 * This function allocates blocks, zeroes out all but the last one,
576 * links them into chain and (if we are synchronous) writes them to disk.
577 * In other words, it prepares a branch that can be spliced onto the
578 * inode. It stores the information about that chain in the branch[], in
579 * the same format as ext3_get_branch() would do. We are calling it after
580 * we had read the existing part of chain and partial points to the last
581 * triple of that (one with zero ->key). Upon the exit we have the same
582 * picture as after the successful ext3_get_block(), except that in one
583 * place chain is disconnected - *branch->p is still zero (we did not
584 * set the last link), but branch->key contains the number that should
585 * be placed into *branch->p to fill that gap.
587 * If allocation fails we free all blocks we've allocated (and forget
588 * their buffer_heads) and return the error value the from failed
589 * ext3_alloc_block() (normally -ENOSPC). Otherwise we set the chain
590 * as described above and return 0.
592 static int ext3_alloc_branch(handle_t
*handle
, struct inode
*inode
,
593 int indirect_blks
, int *blks
, ext3_fsblk_t goal
,
594 int *offsets
, Indirect
*branch
)
596 int blocksize
= inode
->i_sb
->s_blocksize
;
599 struct buffer_head
*bh
;
601 ext3_fsblk_t new_blocks
[4];
602 ext3_fsblk_t current_block
;
604 num
= ext3_alloc_blocks(handle
, inode
, goal
, indirect_blks
,
605 *blks
, new_blocks
, &err
);
609 branch
[0].key
= cpu_to_le32(new_blocks
[0]);
611 * metadata blocks and data blocks are allocated.
613 for (n
= 1; n
<= indirect_blks
; n
++) {
615 * Get buffer_head for parent block, zero it out
616 * and set the pointer to new one, then send
619 bh
= sb_getblk(inode
->i_sb
, new_blocks
[n
-1]);
622 BUFFER_TRACE(bh
, "call get_create_access");
623 err
= ext3_journal_get_create_access(handle
, bh
);
630 memset(bh
->b_data
, 0, blocksize
);
631 branch
[n
].p
= (__le32
*) bh
->b_data
+ offsets
[n
];
632 branch
[n
].key
= cpu_to_le32(new_blocks
[n
]);
633 *branch
[n
].p
= branch
[n
].key
;
634 if ( n
== indirect_blks
) {
635 current_block
= new_blocks
[n
];
637 * End of chain, update the last new metablock of
638 * the chain to point to the new allocated
639 * data blocks numbers
641 for (i
=1; i
< num
; i
++)
642 *(branch
[n
].p
+ i
) = cpu_to_le32(++current_block
);
644 BUFFER_TRACE(bh
, "marking uptodate");
645 set_buffer_uptodate(bh
);
648 BUFFER_TRACE(bh
, "call ext3_journal_dirty_metadata");
649 err
= ext3_journal_dirty_metadata(handle
, bh
);
656 /* Allocation failed, free what we already allocated */
657 for (i
= 1; i
<= n
; i
++) {
658 BUFFER_TRACE(branch
[i
].bh
, "call journal_forget");
659 ext3_journal_forget(handle
, branch
[i
].bh
);
661 for (i
= 0; i
<indirect_blks
; i
++)
662 ext3_free_blocks(handle
, inode
, new_blocks
[i
], 1);
664 ext3_free_blocks(handle
, inode
, new_blocks
[i
], num
);
670 * ext3_splice_branch - splice the allocated branch onto inode.
672 * @block: (logical) number of block we are adding
673 * @chain: chain of indirect blocks (with a missing link - see
675 * @where: location of missing link
676 * @num: number of indirect blocks we are adding
677 * @blks: number of direct blocks we are adding
679 * This function fills the missing link and does all housekeeping needed in
680 * inode (->i_blocks, etc.). In case of success we end up with the full
681 * chain to new block and return 0.
683 static int ext3_splice_branch(handle_t
*handle
, struct inode
*inode
,
684 long block
, Indirect
*where
, int num
, int blks
)
688 struct ext3_block_alloc_info
*block_i
;
689 ext3_fsblk_t current_block
;
691 block_i
= EXT3_I(inode
)->i_block_alloc_info
;
693 * If we're splicing into a [td]indirect block (as opposed to the
694 * inode) then we need to get write access to the [td]indirect block
698 BUFFER_TRACE(where
->bh
, "get_write_access");
699 err
= ext3_journal_get_write_access(handle
, where
->bh
);
705 *where
->p
= where
->key
;
708 * Update the host buffer_head or inode to point to more just allocated
709 * direct blocks blocks
711 if (num
== 0 && blks
> 1) {
712 current_block
= le32_to_cpu(where
->key
) + 1;
713 for (i
= 1; i
< blks
; i
++)
714 *(where
->p
+ i
) = cpu_to_le32(current_block
++);
718 * update the most recently allocated logical & physical block
719 * in i_block_alloc_info, to assist find the proper goal block for next
723 block_i
->last_alloc_logical_block
= block
+ blks
- 1;
724 block_i
->last_alloc_physical_block
=
725 le32_to_cpu(where
[num
].key
) + blks
- 1;
728 /* We are done with atomic stuff, now do the rest of housekeeping */
730 inode
->i_ctime
= CURRENT_TIME_SEC
;
731 ext3_mark_inode_dirty(handle
, inode
);
733 /* had we spliced it onto indirect block? */
736 * If we spliced it onto an indirect block, we haven't
737 * altered the inode. Note however that if it is being spliced
738 * onto an indirect block at the very end of the file (the
739 * file is growing) then we *will* alter the inode to reflect
740 * the new i_size. But that is not done here - it is done in
741 * generic_commit_write->__mark_inode_dirty->ext3_dirty_inode.
743 jbd_debug(5, "splicing indirect only\n");
744 BUFFER_TRACE(where
->bh
, "call ext3_journal_dirty_metadata");
745 err
= ext3_journal_dirty_metadata(handle
, where
->bh
);
750 * OK, we spliced it into the inode itself on a direct block.
751 * Inode was dirtied above.
753 jbd_debug(5, "splicing direct\n");
758 for (i
= 1; i
<= num
; i
++) {
759 BUFFER_TRACE(where
[i
].bh
, "call journal_forget");
760 ext3_journal_forget(handle
, where
[i
].bh
);
761 ext3_free_blocks(handle
,inode
,le32_to_cpu(where
[i
-1].key
),1);
763 ext3_free_blocks(handle
, inode
, le32_to_cpu(where
[num
].key
), blks
);
769 * Allocation strategy is simple: if we have to allocate something, we will
770 * have to go the whole way to leaf. So let's do it before attaching anything
771 * to tree, set linkage between the newborn blocks, write them if sync is
772 * required, recheck the path, free and repeat if check fails, otherwise
773 * set the last missing link (that will protect us from any truncate-generated
774 * removals - all blocks on the path are immune now) and possibly force the
775 * write on the parent block.
776 * That has a nice additional property: no special recovery from the failed
777 * allocations is needed - we simply release blocks and do not touch anything
778 * reachable from inode.
780 * `handle' can be NULL if create == 0.
782 * The BKL may not be held on entry here. Be sure to take it early.
783 * return > 0, # of blocks mapped or allocated.
784 * return = 0, if plain lookup failed.
785 * return < 0, error case.
787 int ext3_get_blocks_handle(handle_t
*handle
, struct inode
*inode
,
788 sector_t iblock
, unsigned long maxblocks
,
789 struct buffer_head
*bh_result
,
790 int create
, int extend_disksize
)
798 int blocks_to_boundary
= 0;
800 struct ext3_inode_info
*ei
= EXT3_I(inode
);
802 ext3_fsblk_t first_block
= 0;
805 J_ASSERT(handle
!= NULL
|| create
== 0);
806 depth
= ext3_block_to_path(inode
,iblock
,offsets
,&blocks_to_boundary
);
811 partial
= ext3_get_branch(inode
, depth
, offsets
, chain
, &err
);
813 /* Simplest case - block found, no allocation needed */
815 first_block
= le32_to_cpu(chain
[depth
- 1].key
);
816 clear_buffer_new(bh_result
);
819 while (count
< maxblocks
&& count
<= blocks_to_boundary
) {
822 if (!verify_chain(chain
, partial
)) {
824 * Indirect block might be removed by
825 * truncate while we were reading it.
826 * Handling of that case: forget what we've
827 * got now. Flag the err as EAGAIN, so it
834 blk
= le32_to_cpu(*(chain
[depth
-1].p
+ count
));
836 if (blk
== first_block
+ count
)
845 /* Next simple case - plain lookup or failed read of indirect block */
846 if (!create
|| err
== -EIO
)
849 mutex_lock(&ei
->truncate_mutex
);
852 * If the indirect block is missing while we are reading
853 * the chain(ext3_get_branch() returns -EAGAIN err), or
854 * if the chain has been changed after we grab the semaphore,
855 * (either because another process truncated this branch, or
856 * another get_block allocated this branch) re-grab the chain to see if
857 * the request block has been allocated or not.
859 * Since we already block the truncate/other get_block
860 * at this point, we will have the current copy of the chain when we
861 * splice the branch into the tree.
863 if (err
== -EAGAIN
|| !verify_chain(chain
, partial
)) {
864 while (partial
> chain
) {
868 partial
= ext3_get_branch(inode
, depth
, offsets
, chain
, &err
);
871 mutex_unlock(&ei
->truncate_mutex
);
874 clear_buffer_new(bh_result
);
880 * Okay, we need to do block allocation. Lazily initialize the block
881 * allocation info here if necessary
883 if (S_ISREG(inode
->i_mode
) && (!ei
->i_block_alloc_info
))
884 ext3_init_block_alloc_info(inode
);
886 goal
= ext3_find_goal(inode
, iblock
, partial
);
888 /* the number of blocks need to allocate for [d,t]indirect blocks */
889 indirect_blks
= (chain
+ depth
) - partial
- 1;
892 * Next look up the indirect map to count the totoal number of
893 * direct blocks to allocate for this branch.
895 count
= ext3_blks_to_allocate(partial
, indirect_blks
,
896 maxblocks
, blocks_to_boundary
);
898 * Block out ext3_truncate while we alter the tree
900 err
= ext3_alloc_branch(handle
, inode
, indirect_blks
, &count
, goal
,
901 offsets
+ (partial
- chain
), partial
);
904 * The ext3_splice_branch call will free and forget any buffers
905 * on the new chain if there is a failure, but that risks using
906 * up transaction credits, especially for bitmaps where the
907 * credits cannot be returned. Can we handle this somehow? We
908 * may need to return -EAGAIN upwards in the worst case. --sct
911 err
= ext3_splice_branch(handle
, inode
, iblock
,
912 partial
, indirect_blks
, count
);
914 * i_disksize growing is protected by truncate_mutex. Don't forget to
915 * protect it if you're about to implement concurrent
916 * ext3_get_block() -bzzz
918 if (!err
&& extend_disksize
&& inode
->i_size
> ei
->i_disksize
)
919 ei
->i_disksize
= inode
->i_size
;
920 mutex_unlock(&ei
->truncate_mutex
);
924 set_buffer_new(bh_result
);
926 map_bh(bh_result
, inode
->i_sb
, le32_to_cpu(chain
[depth
-1].key
));
927 if (count
> blocks_to_boundary
)
928 set_buffer_boundary(bh_result
);
930 /* Clean up and exit */
931 partial
= chain
+ depth
- 1; /* the whole chain */
933 while (partial
> chain
) {
934 BUFFER_TRACE(partial
->bh
, "call brelse");
938 BUFFER_TRACE(bh_result
, "returned");
943 /* Maximum number of blocks we map for direct IO at once. */
944 #define DIO_MAX_BLOCKS 4096
946 * Number of credits we need for writing DIO_MAX_BLOCKS:
947 * We need sb + group descriptor + bitmap + inode -> 4
948 * For B blocks with A block pointers per block we need:
949 * 1 (triple ind.) + (B/A/A + 2) (doubly ind.) + (B/A + 2) (indirect).
950 * If we plug in 4096 for B and 256 for A (for 1KB block size), we get 25.
952 #define DIO_CREDITS 25
954 static int ext3_get_block(struct inode
*inode
, sector_t iblock
,
955 struct buffer_head
*bh_result
, int create
)
957 handle_t
*handle
= ext3_journal_current_handle();
958 int ret
= 0, started
= 0;
959 unsigned max_blocks
= bh_result
->b_size
>> inode
->i_blkbits
;
961 if (create
&& !handle
) { /* Direct IO write... */
962 if (max_blocks
> DIO_MAX_BLOCKS
)
963 max_blocks
= DIO_MAX_BLOCKS
;
964 handle
= ext3_journal_start(inode
, DIO_CREDITS
+
965 2 * EXT3_QUOTA_TRANS_BLOCKS(inode
->i_sb
));
966 if (IS_ERR(handle
)) {
967 ret
= PTR_ERR(handle
);
973 ret
= ext3_get_blocks_handle(handle
, inode
, iblock
,
974 max_blocks
, bh_result
, create
, 0);
976 bh_result
->b_size
= (ret
<< inode
->i_blkbits
);
980 ext3_journal_stop(handle
);
985 int ext3_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
988 return generic_block_fiemap(inode
, fieinfo
, start
, len
,
993 * `handle' can be NULL if create is zero
995 struct buffer_head
*ext3_getblk(handle_t
*handle
, struct inode
*inode
,
996 long block
, int create
, int *errp
)
998 struct buffer_head dummy
;
1001 J_ASSERT(handle
!= NULL
|| create
== 0);
1004 dummy
.b_blocknr
= -1000;
1005 buffer_trace_init(&dummy
.b_history
);
1006 err
= ext3_get_blocks_handle(handle
, inode
, block
, 1,
1009 * ext3_get_blocks_handle() returns number of blocks
1010 * mapped. 0 in case of a HOLE.
1018 if (!err
&& buffer_mapped(&dummy
)) {
1019 struct buffer_head
*bh
;
1020 bh
= sb_getblk(inode
->i_sb
, dummy
.b_blocknr
);
1025 if (buffer_new(&dummy
)) {
1026 J_ASSERT(create
!= 0);
1027 J_ASSERT(handle
!= NULL
);
1030 * Now that we do not always journal data, we should
1031 * keep in mind whether this should always journal the
1032 * new buffer as metadata. For now, regular file
1033 * writes use ext3_get_block instead, so it's not a
1037 BUFFER_TRACE(bh
, "call get_create_access");
1038 fatal
= ext3_journal_get_create_access(handle
, bh
);
1039 if (!fatal
&& !buffer_uptodate(bh
)) {
1040 memset(bh
->b_data
,0,inode
->i_sb
->s_blocksize
);
1041 set_buffer_uptodate(bh
);
1044 BUFFER_TRACE(bh
, "call ext3_journal_dirty_metadata");
1045 err
= ext3_journal_dirty_metadata(handle
, bh
);
1049 BUFFER_TRACE(bh
, "not a new buffer");
1062 struct buffer_head
*ext3_bread(handle_t
*handle
, struct inode
*inode
,
1063 int block
, int create
, int *err
)
1065 struct buffer_head
* bh
;
1067 bh
= ext3_getblk(handle
, inode
, block
, create
, err
);
1070 if (buffer_uptodate(bh
))
1072 ll_rw_block(READ_META
, 1, &bh
);
1074 if (buffer_uptodate(bh
))
1081 static int walk_page_buffers( handle_t
*handle
,
1082 struct buffer_head
*head
,
1086 int (*fn
)( handle_t
*handle
,
1087 struct buffer_head
*bh
))
1089 struct buffer_head
*bh
;
1090 unsigned block_start
, block_end
;
1091 unsigned blocksize
= head
->b_size
;
1093 struct buffer_head
*next
;
1095 for ( bh
= head
, block_start
= 0;
1096 ret
== 0 && (bh
!= head
|| !block_start
);
1097 block_start
= block_end
, bh
= next
)
1099 next
= bh
->b_this_page
;
1100 block_end
= block_start
+ blocksize
;
1101 if (block_end
<= from
|| block_start
>= to
) {
1102 if (partial
&& !buffer_uptodate(bh
))
1106 err
= (*fn
)(handle
, bh
);
1114 * To preserve ordering, it is essential that the hole instantiation and
1115 * the data write be encapsulated in a single transaction. We cannot
1116 * close off a transaction and start a new one between the ext3_get_block()
1117 * and the commit_write(). So doing the journal_start at the start of
1118 * prepare_write() is the right place.
1120 * Also, this function can nest inside ext3_writepage() ->
1121 * block_write_full_page(). In that case, we *know* that ext3_writepage()
1122 * has generated enough buffer credits to do the whole page. So we won't
1123 * block on the journal in that case, which is good, because the caller may
1126 * By accident, ext3 can be reentered when a transaction is open via
1127 * quota file writes. If we were to commit the transaction while thus
1128 * reentered, there can be a deadlock - we would be holding a quota
1129 * lock, and the commit would never complete if another thread had a
1130 * transaction open and was blocking on the quota lock - a ranking
1133 * So what we do is to rely on the fact that journal_stop/journal_start
1134 * will _not_ run commit under these circumstances because handle->h_ref
1135 * is elevated. We'll still have enough credits for the tiny quotafile
1138 static int do_journal_get_write_access(handle_t
*handle
,
1139 struct buffer_head
*bh
)
1141 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1143 return ext3_journal_get_write_access(handle
, bh
);
1146 static int ext3_write_begin(struct file
*file
, struct address_space
*mapping
,
1147 loff_t pos
, unsigned len
, unsigned flags
,
1148 struct page
**pagep
, void **fsdata
)
1150 struct inode
*inode
= mapping
->host
;
1151 int ret
, needed_blocks
= ext3_writepage_trans_blocks(inode
);
1158 index
= pos
>> PAGE_CACHE_SHIFT
;
1159 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1163 page
= __grab_cache_page(mapping
, index
);
1168 handle
= ext3_journal_start(inode
, needed_blocks
);
1169 if (IS_ERR(handle
)) {
1171 page_cache_release(page
);
1172 ret
= PTR_ERR(handle
);
1175 ret
= block_write_begin(file
, mapping
, pos
, len
, flags
, pagep
, fsdata
,
1178 goto write_begin_failed
;
1180 if (ext3_should_journal_data(inode
)) {
1181 ret
= walk_page_buffers(handle
, page_buffers(page
),
1182 from
, to
, NULL
, do_journal_get_write_access
);
1186 ext3_journal_stop(handle
);
1188 page_cache_release(page
);
1190 if (ret
== -ENOSPC
&& ext3_should_retry_alloc(inode
->i_sb
, &retries
))
1197 int ext3_journal_dirty_data(handle_t
*handle
, struct buffer_head
*bh
)
1199 int err
= journal_dirty_data(handle
, bh
);
1201 ext3_journal_abort_handle(__func__
, __func__
,
1206 /* For write_end() in data=journal mode */
1207 static int write_end_fn(handle_t
*handle
, struct buffer_head
*bh
)
1209 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1211 set_buffer_uptodate(bh
);
1212 return ext3_journal_dirty_metadata(handle
, bh
);
1216 * Generic write_end handler for ordered and writeback ext3 journal modes.
1217 * We can't use generic_write_end, because that unlocks the page and we need to
1218 * unlock the page after ext3_journal_stop, but ext3_journal_stop must run
1219 * after block_write_end.
1221 static int ext3_generic_write_end(struct file
*file
,
1222 struct address_space
*mapping
,
1223 loff_t pos
, unsigned len
, unsigned copied
,
1224 struct page
*page
, void *fsdata
)
1226 struct inode
*inode
= file
->f_mapping
->host
;
1228 copied
= block_write_end(file
, mapping
, pos
, len
, copied
, page
, fsdata
);
1230 if (pos
+copied
> inode
->i_size
) {
1231 i_size_write(inode
, pos
+copied
);
1232 mark_inode_dirty(inode
);
1239 * We need to pick up the new inode size which generic_commit_write gave us
1240 * `file' can be NULL - eg, when called from page_symlink().
1242 * ext3 never places buffers on inode->i_mapping->private_list. metadata
1243 * buffers are managed internally.
1245 static int ext3_ordered_write_end(struct file
*file
,
1246 struct address_space
*mapping
,
1247 loff_t pos
, unsigned len
, unsigned copied
,
1248 struct page
*page
, void *fsdata
)
1250 handle_t
*handle
= ext3_journal_current_handle();
1251 struct inode
*inode
= file
->f_mapping
->host
;
1255 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1258 ret
= walk_page_buffers(handle
, page_buffers(page
),
1259 from
, to
, NULL
, ext3_journal_dirty_data
);
1263 * generic_write_end() will run mark_inode_dirty() if i_size
1264 * changes. So let's piggyback the i_disksize mark_inode_dirty
1269 new_i_size
= pos
+ copied
;
1270 if (new_i_size
> EXT3_I(inode
)->i_disksize
)
1271 EXT3_I(inode
)->i_disksize
= new_i_size
;
1272 ret2
= ext3_generic_write_end(file
, mapping
, pos
, len
, copied
,
1278 ret2
= ext3_journal_stop(handle
);
1282 page_cache_release(page
);
1284 return ret
? ret
: copied
;
1287 static int ext3_writeback_write_end(struct file
*file
,
1288 struct address_space
*mapping
,
1289 loff_t pos
, unsigned len
, unsigned copied
,
1290 struct page
*page
, void *fsdata
)
1292 handle_t
*handle
= ext3_journal_current_handle();
1293 struct inode
*inode
= file
->f_mapping
->host
;
1297 new_i_size
= pos
+ copied
;
1298 if (new_i_size
> EXT3_I(inode
)->i_disksize
)
1299 EXT3_I(inode
)->i_disksize
= new_i_size
;
1301 ret2
= ext3_generic_write_end(file
, mapping
, pos
, len
, copied
,
1307 ret2
= ext3_journal_stop(handle
);
1311 page_cache_release(page
);
1313 return ret
? ret
: copied
;
1316 static int ext3_journalled_write_end(struct file
*file
,
1317 struct address_space
*mapping
,
1318 loff_t pos
, unsigned len
, unsigned copied
,
1319 struct page
*page
, void *fsdata
)
1321 handle_t
*handle
= ext3_journal_current_handle();
1322 struct inode
*inode
= mapping
->host
;
1327 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1331 if (!PageUptodate(page
))
1333 page_zero_new_buffers(page
, from
+copied
, to
);
1336 ret
= walk_page_buffers(handle
, page_buffers(page
), from
,
1337 to
, &partial
, write_end_fn
);
1339 SetPageUptodate(page
);
1340 if (pos
+copied
> inode
->i_size
)
1341 i_size_write(inode
, pos
+copied
);
1342 EXT3_I(inode
)->i_state
|= EXT3_STATE_JDATA
;
1343 if (inode
->i_size
> EXT3_I(inode
)->i_disksize
) {
1344 EXT3_I(inode
)->i_disksize
= inode
->i_size
;
1345 ret2
= ext3_mark_inode_dirty(handle
, inode
);
1350 ret2
= ext3_journal_stop(handle
);
1354 page_cache_release(page
);
1356 return ret
? ret
: copied
;
1360 * bmap() is special. It gets used by applications such as lilo and by
1361 * the swapper to find the on-disk block of a specific piece of data.
1363 * Naturally, this is dangerous if the block concerned is still in the
1364 * journal. If somebody makes a swapfile on an ext3 data-journaling
1365 * filesystem and enables swap, then they may get a nasty shock when the
1366 * data getting swapped to that swapfile suddenly gets overwritten by
1367 * the original zero's written out previously to the journal and
1368 * awaiting writeback in the kernel's buffer cache.
1370 * So, if we see any bmap calls here on a modified, data-journaled file,
1371 * take extra steps to flush any blocks which might be in the cache.
1373 static sector_t
ext3_bmap(struct address_space
*mapping
, sector_t block
)
1375 struct inode
*inode
= mapping
->host
;
1379 if (EXT3_I(inode
)->i_state
& EXT3_STATE_JDATA
) {
1381 * This is a REALLY heavyweight approach, but the use of
1382 * bmap on dirty files is expected to be extremely rare:
1383 * only if we run lilo or swapon on a freshly made file
1384 * do we expect this to happen.
1386 * (bmap requires CAP_SYS_RAWIO so this does not
1387 * represent an unprivileged user DOS attack --- we'd be
1388 * in trouble if mortal users could trigger this path at
1391 * NB. EXT3_STATE_JDATA is not set on files other than
1392 * regular files. If somebody wants to bmap a directory
1393 * or symlink and gets confused because the buffer
1394 * hasn't yet been flushed to disk, they deserve
1395 * everything they get.
1398 EXT3_I(inode
)->i_state
&= ~EXT3_STATE_JDATA
;
1399 journal
= EXT3_JOURNAL(inode
);
1400 journal_lock_updates(journal
);
1401 err
= journal_flush(journal
);
1402 journal_unlock_updates(journal
);
1408 return generic_block_bmap(mapping
,block
,ext3_get_block
);
1411 static int bget_one(handle_t
*handle
, struct buffer_head
*bh
)
1417 static int bput_one(handle_t
*handle
, struct buffer_head
*bh
)
1423 static int journal_dirty_data_fn(handle_t
*handle
, struct buffer_head
*bh
)
1425 if (buffer_mapped(bh
))
1426 return ext3_journal_dirty_data(handle
, bh
);
1431 * Note that we always start a transaction even if we're not journalling
1432 * data. This is to preserve ordering: any hole instantiation within
1433 * __block_write_full_page -> ext3_get_block() should be journalled
1434 * along with the data so we don't crash and then get metadata which
1435 * refers to old data.
1437 * In all journalling modes block_write_full_page() will start the I/O.
1441 * ext3_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
1446 * ext3_file_write() -> generic_file_write() -> __alloc_pages() -> ...
1448 * Same applies to ext3_get_block(). We will deadlock on various things like
1449 * lock_journal and i_truncate_mutex.
1451 * Setting PF_MEMALLOC here doesn't work - too many internal memory
1454 * 16May01: If we're reentered then journal_current_handle() will be
1455 * non-zero. We simply *return*.
1457 * 1 July 2001: @@@ FIXME:
1458 * In journalled data mode, a data buffer may be metadata against the
1459 * current transaction. But the same file is part of a shared mapping
1460 * and someone does a writepage() on it.
1462 * We will move the buffer onto the async_data list, but *after* it has
1463 * been dirtied. So there's a small window where we have dirty data on
1466 * Note that this only applies to the last partial page in the file. The
1467 * bit which block_write_full_page() uses prepare/commit for. (That's
1468 * broken code anyway: it's wrong for msync()).
1470 * It's a rare case: affects the final partial page, for journalled data
1471 * where the file is subject to bith write() and writepage() in the same
1472 * transction. To fix it we'll need a custom block_write_full_page().
1473 * We'll probably need that anyway for journalling writepage() output.
1475 * We don't honour synchronous mounts for writepage(). That would be
1476 * disastrous. Any write() or metadata operation will sync the fs for
1479 * AKPM2: if all the page's buffers are mapped to disk and !data=journal,
1480 * we don't need to open a transaction here.
1482 static int ext3_ordered_writepage(struct page
*page
,
1483 struct writeback_control
*wbc
)
1485 struct inode
*inode
= page
->mapping
->host
;
1486 struct buffer_head
*page_bufs
;
1487 handle_t
*handle
= NULL
;
1491 J_ASSERT(PageLocked(page
));
1494 * We give up here if we're reentered, because it might be for a
1495 * different filesystem.
1497 if (ext3_journal_current_handle())
1500 handle
= ext3_journal_start(inode
, ext3_writepage_trans_blocks(inode
));
1502 if (IS_ERR(handle
)) {
1503 ret
= PTR_ERR(handle
);
1507 if (!page_has_buffers(page
)) {
1508 create_empty_buffers(page
, inode
->i_sb
->s_blocksize
,
1509 (1 << BH_Dirty
)|(1 << BH_Uptodate
));
1511 page_bufs
= page_buffers(page
);
1512 walk_page_buffers(handle
, page_bufs
, 0,
1513 PAGE_CACHE_SIZE
, NULL
, bget_one
);
1515 ret
= block_write_full_page(page
, ext3_get_block
, wbc
);
1518 * The page can become unlocked at any point now, and
1519 * truncate can then come in and change things. So we
1520 * can't touch *page from now on. But *page_bufs is
1521 * safe due to elevated refcount.
1525 * And attach them to the current transaction. But only if
1526 * block_write_full_page() succeeded. Otherwise they are unmapped,
1527 * and generally junk.
1530 err
= walk_page_buffers(handle
, page_bufs
, 0, PAGE_CACHE_SIZE
,
1531 NULL
, journal_dirty_data_fn
);
1535 walk_page_buffers(handle
, page_bufs
, 0,
1536 PAGE_CACHE_SIZE
, NULL
, bput_one
);
1537 err
= ext3_journal_stop(handle
);
1543 redirty_page_for_writepage(wbc
, page
);
1548 static int ext3_writeback_writepage(struct page
*page
,
1549 struct writeback_control
*wbc
)
1551 struct inode
*inode
= page
->mapping
->host
;
1552 handle_t
*handle
= NULL
;
1556 if (ext3_journal_current_handle())
1559 handle
= ext3_journal_start(inode
, ext3_writepage_trans_blocks(inode
));
1560 if (IS_ERR(handle
)) {
1561 ret
= PTR_ERR(handle
);
1565 if (test_opt(inode
->i_sb
, NOBH
) && ext3_should_writeback_data(inode
))
1566 ret
= nobh_writepage(page
, ext3_get_block
, wbc
);
1568 ret
= block_write_full_page(page
, ext3_get_block
, wbc
);
1570 err
= ext3_journal_stop(handle
);
1576 redirty_page_for_writepage(wbc
, page
);
1581 static int ext3_journalled_writepage(struct page
*page
,
1582 struct writeback_control
*wbc
)
1584 struct inode
*inode
= page
->mapping
->host
;
1585 handle_t
*handle
= NULL
;
1589 if (ext3_journal_current_handle())
1592 handle
= ext3_journal_start(inode
, ext3_writepage_trans_blocks(inode
));
1593 if (IS_ERR(handle
)) {
1594 ret
= PTR_ERR(handle
);
1598 if (!page_has_buffers(page
) || PageChecked(page
)) {
1600 * It's mmapped pagecache. Add buffers and journal it. There
1601 * doesn't seem much point in redirtying the page here.
1603 ClearPageChecked(page
);
1604 ret
= block_prepare_write(page
, 0, PAGE_CACHE_SIZE
,
1607 ext3_journal_stop(handle
);
1610 ret
= walk_page_buffers(handle
, page_buffers(page
), 0,
1611 PAGE_CACHE_SIZE
, NULL
, do_journal_get_write_access
);
1613 err
= walk_page_buffers(handle
, page_buffers(page
), 0,
1614 PAGE_CACHE_SIZE
, NULL
, write_end_fn
);
1617 EXT3_I(inode
)->i_state
|= EXT3_STATE_JDATA
;
1621 * It may be a page full of checkpoint-mode buffers. We don't
1622 * really know unless we go poke around in the buffer_heads.
1623 * But block_write_full_page will do the right thing.
1625 ret
= block_write_full_page(page
, ext3_get_block
, wbc
);
1627 err
= ext3_journal_stop(handle
);
1634 redirty_page_for_writepage(wbc
, page
);
1640 static int ext3_readpage(struct file
*file
, struct page
*page
)
1642 return mpage_readpage(page
, ext3_get_block
);
1646 ext3_readpages(struct file
*file
, struct address_space
*mapping
,
1647 struct list_head
*pages
, unsigned nr_pages
)
1649 return mpage_readpages(mapping
, pages
, nr_pages
, ext3_get_block
);
1652 static void ext3_invalidatepage(struct page
*page
, unsigned long offset
)
1654 journal_t
*journal
= EXT3_JOURNAL(page
->mapping
->host
);
1657 * If it's a full truncate we just forget about the pending dirtying
1660 ClearPageChecked(page
);
1662 journal_invalidatepage(journal
, page
, offset
);
1665 static int ext3_releasepage(struct page
*page
, gfp_t wait
)
1667 journal_t
*journal
= EXT3_JOURNAL(page
->mapping
->host
);
1669 WARN_ON(PageChecked(page
));
1670 if (!page_has_buffers(page
))
1672 return journal_try_to_free_buffers(journal
, page
, wait
);
1676 * If the O_DIRECT write will extend the file then add this inode to the
1677 * orphan list. So recovery will truncate it back to the original size
1678 * if the machine crashes during the write.
1680 * If the O_DIRECT write is intantiating holes inside i_size and the machine
1681 * crashes then stale disk data _may_ be exposed inside the file. But current
1682 * VFS code falls back into buffered path in that case so we are safe.
1684 static ssize_t
ext3_direct_IO(int rw
, struct kiocb
*iocb
,
1685 const struct iovec
*iov
, loff_t offset
,
1686 unsigned long nr_segs
)
1688 struct file
*file
= iocb
->ki_filp
;
1689 struct inode
*inode
= file
->f_mapping
->host
;
1690 struct ext3_inode_info
*ei
= EXT3_I(inode
);
1694 size_t count
= iov_length(iov
, nr_segs
);
1697 loff_t final_size
= offset
+ count
;
1699 if (final_size
> inode
->i_size
) {
1700 /* Credits for sb + inode write */
1701 handle
= ext3_journal_start(inode
, 2);
1702 if (IS_ERR(handle
)) {
1703 ret
= PTR_ERR(handle
);
1706 ret
= ext3_orphan_add(handle
, inode
);
1708 ext3_journal_stop(handle
);
1712 ei
->i_disksize
= inode
->i_size
;
1713 ext3_journal_stop(handle
);
1717 ret
= blockdev_direct_IO(rw
, iocb
, inode
, inode
->i_sb
->s_bdev
, iov
,
1719 ext3_get_block
, NULL
);
1724 /* Credits for sb + inode write */
1725 handle
= ext3_journal_start(inode
, 2);
1726 if (IS_ERR(handle
)) {
1727 /* This is really bad luck. We've written the data
1728 * but cannot extend i_size. Bail out and pretend
1729 * the write failed... */
1730 ret
= PTR_ERR(handle
);
1734 ext3_orphan_del(handle
, inode
);
1736 loff_t end
= offset
+ ret
;
1737 if (end
> inode
->i_size
) {
1738 ei
->i_disksize
= end
;
1739 i_size_write(inode
, end
);
1741 * We're going to return a positive `ret'
1742 * here due to non-zero-length I/O, so there's
1743 * no way of reporting error returns from
1744 * ext3_mark_inode_dirty() to userspace. So
1747 ext3_mark_inode_dirty(handle
, inode
);
1750 err
= ext3_journal_stop(handle
);
1759 * Pages can be marked dirty completely asynchronously from ext3's journalling
1760 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
1761 * much here because ->set_page_dirty is called under VFS locks. The page is
1762 * not necessarily locked.
1764 * We cannot just dirty the page and leave attached buffers clean, because the
1765 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
1766 * or jbddirty because all the journalling code will explode.
1768 * So what we do is to mark the page "pending dirty" and next time writepage
1769 * is called, propagate that into the buffers appropriately.
1771 static int ext3_journalled_set_page_dirty(struct page
*page
)
1773 SetPageChecked(page
);
1774 return __set_page_dirty_nobuffers(page
);
1777 static const struct address_space_operations ext3_ordered_aops
= {
1778 .readpage
= ext3_readpage
,
1779 .readpages
= ext3_readpages
,
1780 .writepage
= ext3_ordered_writepage
,
1781 .sync_page
= block_sync_page
,
1782 .write_begin
= ext3_write_begin
,
1783 .write_end
= ext3_ordered_write_end
,
1785 .invalidatepage
= ext3_invalidatepage
,
1786 .releasepage
= ext3_releasepage
,
1787 .direct_IO
= ext3_direct_IO
,
1788 .migratepage
= buffer_migrate_page
,
1789 .is_partially_uptodate
= block_is_partially_uptodate
,
1792 static const struct address_space_operations ext3_writeback_aops
= {
1793 .readpage
= ext3_readpage
,
1794 .readpages
= ext3_readpages
,
1795 .writepage
= ext3_writeback_writepage
,
1796 .sync_page
= block_sync_page
,
1797 .write_begin
= ext3_write_begin
,
1798 .write_end
= ext3_writeback_write_end
,
1800 .invalidatepage
= ext3_invalidatepage
,
1801 .releasepage
= ext3_releasepage
,
1802 .direct_IO
= ext3_direct_IO
,
1803 .migratepage
= buffer_migrate_page
,
1804 .is_partially_uptodate
= block_is_partially_uptodate
,
1807 static const struct address_space_operations ext3_journalled_aops
= {
1808 .readpage
= ext3_readpage
,
1809 .readpages
= ext3_readpages
,
1810 .writepage
= ext3_journalled_writepage
,
1811 .sync_page
= block_sync_page
,
1812 .write_begin
= ext3_write_begin
,
1813 .write_end
= ext3_journalled_write_end
,
1814 .set_page_dirty
= ext3_journalled_set_page_dirty
,
1816 .invalidatepage
= ext3_invalidatepage
,
1817 .releasepage
= ext3_releasepage
,
1818 .is_partially_uptodate
= block_is_partially_uptodate
,
1821 void ext3_set_aops(struct inode
*inode
)
1823 if (ext3_should_order_data(inode
))
1824 inode
->i_mapping
->a_ops
= &ext3_ordered_aops
;
1825 else if (ext3_should_writeback_data(inode
))
1826 inode
->i_mapping
->a_ops
= &ext3_writeback_aops
;
1828 inode
->i_mapping
->a_ops
= &ext3_journalled_aops
;
1832 * ext3_block_truncate_page() zeroes out a mapping from file offset `from'
1833 * up to the end of the block which corresponds to `from'.
1834 * This required during truncate. We need to physically zero the tail end
1835 * of that block so it doesn't yield old data if the file is later grown.
1837 static int ext3_block_truncate_page(handle_t
*handle
, struct page
*page
,
1838 struct address_space
*mapping
, loff_t from
)
1840 ext3_fsblk_t index
= from
>> PAGE_CACHE_SHIFT
;
1841 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
1842 unsigned blocksize
, iblock
, length
, pos
;
1843 struct inode
*inode
= mapping
->host
;
1844 struct buffer_head
*bh
;
1847 blocksize
= inode
->i_sb
->s_blocksize
;
1848 length
= blocksize
- (offset
& (blocksize
- 1));
1849 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
1852 * For "nobh" option, we can only work if we don't need to
1853 * read-in the page - otherwise we create buffers to do the IO.
1855 if (!page_has_buffers(page
) && test_opt(inode
->i_sb
, NOBH
) &&
1856 ext3_should_writeback_data(inode
) && PageUptodate(page
)) {
1857 zero_user(page
, offset
, length
);
1858 set_page_dirty(page
);
1862 if (!page_has_buffers(page
))
1863 create_empty_buffers(page
, blocksize
, 0);
1865 /* Find the buffer that contains "offset" */
1866 bh
= page_buffers(page
);
1868 while (offset
>= pos
) {
1869 bh
= bh
->b_this_page
;
1875 if (buffer_freed(bh
)) {
1876 BUFFER_TRACE(bh
, "freed: skip");
1880 if (!buffer_mapped(bh
)) {
1881 BUFFER_TRACE(bh
, "unmapped");
1882 ext3_get_block(inode
, iblock
, bh
, 0);
1883 /* unmapped? It's a hole - nothing to do */
1884 if (!buffer_mapped(bh
)) {
1885 BUFFER_TRACE(bh
, "still unmapped");
1890 /* Ok, it's mapped. Make sure it's up-to-date */
1891 if (PageUptodate(page
))
1892 set_buffer_uptodate(bh
);
1894 if (!buffer_uptodate(bh
)) {
1896 ll_rw_block(READ
, 1, &bh
);
1898 /* Uhhuh. Read error. Complain and punt. */
1899 if (!buffer_uptodate(bh
))
1903 if (ext3_should_journal_data(inode
)) {
1904 BUFFER_TRACE(bh
, "get write access");
1905 err
= ext3_journal_get_write_access(handle
, bh
);
1910 zero_user(page
, offset
, length
);
1911 BUFFER_TRACE(bh
, "zeroed end of block");
1914 if (ext3_should_journal_data(inode
)) {
1915 err
= ext3_journal_dirty_metadata(handle
, bh
);
1917 if (ext3_should_order_data(inode
))
1918 err
= ext3_journal_dirty_data(handle
, bh
);
1919 mark_buffer_dirty(bh
);
1924 page_cache_release(page
);
1929 * Probably it should be a library function... search for first non-zero word
1930 * or memcmp with zero_page, whatever is better for particular architecture.
1933 static inline int all_zeroes(__le32
*p
, __le32
*q
)
1942 * ext3_find_shared - find the indirect blocks for partial truncation.
1943 * @inode: inode in question
1944 * @depth: depth of the affected branch
1945 * @offsets: offsets of pointers in that branch (see ext3_block_to_path)
1946 * @chain: place to store the pointers to partial indirect blocks
1947 * @top: place to the (detached) top of branch
1949 * This is a helper function used by ext3_truncate().
1951 * When we do truncate() we may have to clean the ends of several
1952 * indirect blocks but leave the blocks themselves alive. Block is
1953 * partially truncated if some data below the new i_size is refered
1954 * from it (and it is on the path to the first completely truncated
1955 * data block, indeed). We have to free the top of that path along
1956 * with everything to the right of the path. Since no allocation
1957 * past the truncation point is possible until ext3_truncate()
1958 * finishes, we may safely do the latter, but top of branch may
1959 * require special attention - pageout below the truncation point
1960 * might try to populate it.
1962 * We atomically detach the top of branch from the tree, store the
1963 * block number of its root in *@top, pointers to buffer_heads of
1964 * partially truncated blocks - in @chain[].bh and pointers to
1965 * their last elements that should not be removed - in
1966 * @chain[].p. Return value is the pointer to last filled element
1969 * The work left to caller to do the actual freeing of subtrees:
1970 * a) free the subtree starting from *@top
1971 * b) free the subtrees whose roots are stored in
1972 * (@chain[i].p+1 .. end of @chain[i].bh->b_data)
1973 * c) free the subtrees growing from the inode past the @chain[0].
1974 * (no partially truncated stuff there). */
1976 static Indirect
*ext3_find_shared(struct inode
*inode
, int depth
,
1977 int offsets
[4], Indirect chain
[4], __le32
*top
)
1979 Indirect
*partial
, *p
;
1983 /* Make k index the deepest non-null offest + 1 */
1984 for (k
= depth
; k
> 1 && !offsets
[k
-1]; k
--)
1986 partial
= ext3_get_branch(inode
, k
, offsets
, chain
, &err
);
1987 /* Writer: pointers */
1989 partial
= chain
+ k
-1;
1991 * If the branch acquired continuation since we've looked at it -
1992 * fine, it should all survive and (new) top doesn't belong to us.
1994 if (!partial
->key
&& *partial
->p
)
1997 for (p
=partial
; p
>chain
&& all_zeroes((__le32
*)p
->bh
->b_data
,p
->p
); p
--)
2000 * OK, we've found the last block that must survive. The rest of our
2001 * branch should be detached before unlocking. However, if that rest
2002 * of branch is all ours and does not grow immediately from the inode
2003 * it's easier to cheat and just decrement partial->p.
2005 if (p
== chain
+ k
- 1 && p
> chain
) {
2009 /* Nope, don't do this in ext3. Must leave the tree intact */
2016 while(partial
> p
) {
2017 brelse(partial
->bh
);
2025 * Zero a number of block pointers in either an inode or an indirect block.
2026 * If we restart the transaction we must again get write access to the
2027 * indirect block for further modification.
2029 * We release `count' blocks on disk, but (last - first) may be greater
2030 * than `count' because there can be holes in there.
2032 static void ext3_clear_blocks(handle_t
*handle
, struct inode
*inode
,
2033 struct buffer_head
*bh
, ext3_fsblk_t block_to_free
,
2034 unsigned long count
, __le32
*first
, __le32
*last
)
2037 if (try_to_extend_transaction(handle
, inode
)) {
2039 BUFFER_TRACE(bh
, "call ext3_journal_dirty_metadata");
2040 ext3_journal_dirty_metadata(handle
, bh
);
2042 ext3_mark_inode_dirty(handle
, inode
);
2043 ext3_journal_test_restart(handle
, inode
);
2045 BUFFER_TRACE(bh
, "retaking write access");
2046 ext3_journal_get_write_access(handle
, bh
);
2051 * Any buffers which are on the journal will be in memory. We find
2052 * them on the hash table so journal_revoke() will run journal_forget()
2053 * on them. We've already detached each block from the file, so
2054 * bforget() in journal_forget() should be safe.
2056 * AKPM: turn on bforget in journal_forget()!!!
2058 for (p
= first
; p
< last
; p
++) {
2059 u32 nr
= le32_to_cpu(*p
);
2061 struct buffer_head
*bh
;
2064 bh
= sb_find_get_block(inode
->i_sb
, nr
);
2065 ext3_forget(handle
, 0, inode
, bh
, nr
);
2069 ext3_free_blocks(handle
, inode
, block_to_free
, count
);
2073 * ext3_free_data - free a list of data blocks
2074 * @handle: handle for this transaction
2075 * @inode: inode we are dealing with
2076 * @this_bh: indirect buffer_head which contains *@first and *@last
2077 * @first: array of block numbers
2078 * @last: points immediately past the end of array
2080 * We are freeing all blocks refered from that array (numbers are stored as
2081 * little-endian 32-bit) and updating @inode->i_blocks appropriately.
2083 * We accumulate contiguous runs of blocks to free. Conveniently, if these
2084 * blocks are contiguous then releasing them at one time will only affect one
2085 * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't
2086 * actually use a lot of journal space.
2088 * @this_bh will be %NULL if @first and @last point into the inode's direct
2091 static void ext3_free_data(handle_t
*handle
, struct inode
*inode
,
2092 struct buffer_head
*this_bh
,
2093 __le32
*first
, __le32
*last
)
2095 ext3_fsblk_t block_to_free
= 0; /* Starting block # of a run */
2096 unsigned long count
= 0; /* Number of blocks in the run */
2097 __le32
*block_to_free_p
= NULL
; /* Pointer into inode/ind
2100 ext3_fsblk_t nr
; /* Current block # */
2101 __le32
*p
; /* Pointer into inode/ind
2102 for current block */
2105 if (this_bh
) { /* For indirect block */
2106 BUFFER_TRACE(this_bh
, "get_write_access");
2107 err
= ext3_journal_get_write_access(handle
, this_bh
);
2108 /* Important: if we can't update the indirect pointers
2109 * to the blocks, we can't free them. */
2114 for (p
= first
; p
< last
; p
++) {
2115 nr
= le32_to_cpu(*p
);
2117 /* accumulate blocks to free if they're contiguous */
2120 block_to_free_p
= p
;
2122 } else if (nr
== block_to_free
+ count
) {
2125 ext3_clear_blocks(handle
, inode
, this_bh
,
2127 count
, block_to_free_p
, p
);
2129 block_to_free_p
= p
;
2136 ext3_clear_blocks(handle
, inode
, this_bh
, block_to_free
,
2137 count
, block_to_free_p
, p
);
2140 BUFFER_TRACE(this_bh
, "call ext3_journal_dirty_metadata");
2143 * The buffer head should have an attached journal head at this
2144 * point. However, if the data is corrupted and an indirect
2145 * block pointed to itself, it would have been detached when
2146 * the block was cleared. Check for this instead of OOPSing.
2149 ext3_journal_dirty_metadata(handle
, this_bh
);
2151 ext3_error(inode
->i_sb
, "ext3_free_data",
2152 "circular indirect block detected, "
2153 "inode=%lu, block=%llu",
2155 (unsigned long long)this_bh
->b_blocknr
);
2160 * ext3_free_branches - free an array of branches
2161 * @handle: JBD handle for this transaction
2162 * @inode: inode we are dealing with
2163 * @parent_bh: the buffer_head which contains *@first and *@last
2164 * @first: array of block numbers
2165 * @last: pointer immediately past the end of array
2166 * @depth: depth of the branches to free
2168 * We are freeing all blocks refered from these branches (numbers are
2169 * stored as little-endian 32-bit) and updating @inode->i_blocks
2172 static void ext3_free_branches(handle_t
*handle
, struct inode
*inode
,
2173 struct buffer_head
*parent_bh
,
2174 __le32
*first
, __le32
*last
, int depth
)
2179 if (is_handle_aborted(handle
))
2183 struct buffer_head
*bh
;
2184 int addr_per_block
= EXT3_ADDR_PER_BLOCK(inode
->i_sb
);
2186 while (--p
>= first
) {
2187 nr
= le32_to_cpu(*p
);
2189 continue; /* A hole */
2191 /* Go read the buffer for the next level down */
2192 bh
= sb_bread(inode
->i_sb
, nr
);
2195 * A read failure? Report error and clear slot
2199 ext3_error(inode
->i_sb
, "ext3_free_branches",
2200 "Read failure, inode=%lu, block="E3FSBLK
,
2205 /* This zaps the entire block. Bottom up. */
2206 BUFFER_TRACE(bh
, "free child branches");
2207 ext3_free_branches(handle
, inode
, bh
,
2208 (__le32
*)bh
->b_data
,
2209 (__le32
*)bh
->b_data
+ addr_per_block
,
2213 * We've probably journalled the indirect block several
2214 * times during the truncate. But it's no longer
2215 * needed and we now drop it from the transaction via
2218 * That's easy if it's exclusively part of this
2219 * transaction. But if it's part of the committing
2220 * transaction then journal_forget() will simply
2221 * brelse() it. That means that if the underlying
2222 * block is reallocated in ext3_get_block(),
2223 * unmap_underlying_metadata() will find this block
2224 * and will try to get rid of it. damn, damn.
2226 * If this block has already been committed to the
2227 * journal, a revoke record will be written. And
2228 * revoke records must be emitted *before* clearing
2229 * this block's bit in the bitmaps.
2231 ext3_forget(handle
, 1, inode
, bh
, bh
->b_blocknr
);
2234 * Everything below this this pointer has been
2235 * released. Now let this top-of-subtree go.
2237 * We want the freeing of this indirect block to be
2238 * atomic in the journal with the updating of the
2239 * bitmap block which owns it. So make some room in
2242 * We zero the parent pointer *after* freeing its
2243 * pointee in the bitmaps, so if extend_transaction()
2244 * for some reason fails to put the bitmap changes and
2245 * the release into the same transaction, recovery
2246 * will merely complain about releasing a free block,
2247 * rather than leaking blocks.
2249 if (is_handle_aborted(handle
))
2251 if (try_to_extend_transaction(handle
, inode
)) {
2252 ext3_mark_inode_dirty(handle
, inode
);
2253 ext3_journal_test_restart(handle
, inode
);
2256 ext3_free_blocks(handle
, inode
, nr
, 1);
2260 * The block which we have just freed is
2261 * pointed to by an indirect block: journal it
2263 BUFFER_TRACE(parent_bh
, "get_write_access");
2264 if (!ext3_journal_get_write_access(handle
,
2267 BUFFER_TRACE(parent_bh
,
2268 "call ext3_journal_dirty_metadata");
2269 ext3_journal_dirty_metadata(handle
,
2275 /* We have reached the bottom of the tree. */
2276 BUFFER_TRACE(parent_bh
, "free data blocks");
2277 ext3_free_data(handle
, inode
, parent_bh
, first
, last
);
2281 int ext3_can_truncate(struct inode
*inode
)
2283 if (IS_APPEND(inode
) || IS_IMMUTABLE(inode
))
2285 if (S_ISREG(inode
->i_mode
))
2287 if (S_ISDIR(inode
->i_mode
))
2289 if (S_ISLNK(inode
->i_mode
))
2290 return !ext3_inode_is_fast_symlink(inode
);
2297 * We block out ext3_get_block() block instantiations across the entire
2298 * transaction, and VFS/VM ensures that ext3_truncate() cannot run
2299 * simultaneously on behalf of the same inode.
2301 * As we work through the truncate and commmit bits of it to the journal there
2302 * is one core, guiding principle: the file's tree must always be consistent on
2303 * disk. We must be able to restart the truncate after a crash.
2305 * The file's tree may be transiently inconsistent in memory (although it
2306 * probably isn't), but whenever we close off and commit a journal transaction,
2307 * the contents of (the filesystem + the journal) must be consistent and
2308 * restartable. It's pretty simple, really: bottom up, right to left (although
2309 * left-to-right works OK too).
2311 * Note that at recovery time, journal replay occurs *before* the restart of
2312 * truncate against the orphan inode list.
2314 * The committed inode has the new, desired i_size (which is the same as
2315 * i_disksize in this case). After a crash, ext3_orphan_cleanup() will see
2316 * that this inode's truncate did not complete and it will again call
2317 * ext3_truncate() to have another go. So there will be instantiated blocks
2318 * to the right of the truncation point in a crashed ext3 filesystem. But
2319 * that's fine - as long as they are linked from the inode, the post-crash
2320 * ext3_truncate() run will find them and release them.
2322 void ext3_truncate(struct inode
*inode
)
2325 struct ext3_inode_info
*ei
= EXT3_I(inode
);
2326 __le32
*i_data
= ei
->i_data
;
2327 int addr_per_block
= EXT3_ADDR_PER_BLOCK(inode
->i_sb
);
2328 struct address_space
*mapping
= inode
->i_mapping
;
2335 unsigned blocksize
= inode
->i_sb
->s_blocksize
;
2338 if (!ext3_can_truncate(inode
))
2342 * We have to lock the EOF page here, because lock_page() nests
2343 * outside journal_start().
2345 if ((inode
->i_size
& (blocksize
- 1)) == 0) {
2346 /* Block boundary? Nothing to do */
2349 page
= grab_cache_page(mapping
,
2350 inode
->i_size
>> PAGE_CACHE_SHIFT
);
2355 handle
= start_transaction(inode
);
2356 if (IS_ERR(handle
)) {
2358 clear_highpage(page
);
2359 flush_dcache_page(page
);
2361 page_cache_release(page
);
2363 return; /* AKPM: return what? */
2366 last_block
= (inode
->i_size
+ blocksize
-1)
2367 >> EXT3_BLOCK_SIZE_BITS(inode
->i_sb
);
2370 ext3_block_truncate_page(handle
, page
, mapping
, inode
->i_size
);
2372 n
= ext3_block_to_path(inode
, last_block
, offsets
, NULL
);
2374 goto out_stop
; /* error */
2377 * OK. This truncate is going to happen. We add the inode to the
2378 * orphan list, so that if this truncate spans multiple transactions,
2379 * and we crash, we will resume the truncate when the filesystem
2380 * recovers. It also marks the inode dirty, to catch the new size.
2382 * Implication: the file must always be in a sane, consistent
2383 * truncatable state while each transaction commits.
2385 if (ext3_orphan_add(handle
, inode
))
2389 * The orphan list entry will now protect us from any crash which
2390 * occurs before the truncate completes, so it is now safe to propagate
2391 * the new, shorter inode size (held for now in i_size) into the
2392 * on-disk inode. We do this via i_disksize, which is the value which
2393 * ext3 *really* writes onto the disk inode.
2395 ei
->i_disksize
= inode
->i_size
;
2398 * From here we block out all ext3_get_block() callers who want to
2399 * modify the block allocation tree.
2401 mutex_lock(&ei
->truncate_mutex
);
2403 if (n
== 1) { /* direct blocks */
2404 ext3_free_data(handle
, inode
, NULL
, i_data
+offsets
[0],
2405 i_data
+ EXT3_NDIR_BLOCKS
);
2409 partial
= ext3_find_shared(inode
, n
, offsets
, chain
, &nr
);
2410 /* Kill the top of shared branch (not detached) */
2412 if (partial
== chain
) {
2413 /* Shared branch grows from the inode */
2414 ext3_free_branches(handle
, inode
, NULL
,
2415 &nr
, &nr
+1, (chain
+n
-1) - partial
);
2418 * We mark the inode dirty prior to restart,
2419 * and prior to stop. No need for it here.
2422 /* Shared branch grows from an indirect block */
2423 BUFFER_TRACE(partial
->bh
, "get_write_access");
2424 ext3_free_branches(handle
, inode
, partial
->bh
,
2426 partial
->p
+1, (chain
+n
-1) - partial
);
2429 /* Clear the ends of indirect blocks on the shared branch */
2430 while (partial
> chain
) {
2431 ext3_free_branches(handle
, inode
, partial
->bh
, partial
->p
+ 1,
2432 (__le32
*)partial
->bh
->b_data
+addr_per_block
,
2433 (chain
+n
-1) - partial
);
2434 BUFFER_TRACE(partial
->bh
, "call brelse");
2435 brelse (partial
->bh
);
2439 /* Kill the remaining (whole) subtrees */
2440 switch (offsets
[0]) {
2442 nr
= i_data
[EXT3_IND_BLOCK
];
2444 ext3_free_branches(handle
, inode
, NULL
, &nr
, &nr
+1, 1);
2445 i_data
[EXT3_IND_BLOCK
] = 0;
2447 case EXT3_IND_BLOCK
:
2448 nr
= i_data
[EXT3_DIND_BLOCK
];
2450 ext3_free_branches(handle
, inode
, NULL
, &nr
, &nr
+1, 2);
2451 i_data
[EXT3_DIND_BLOCK
] = 0;
2453 case EXT3_DIND_BLOCK
:
2454 nr
= i_data
[EXT3_TIND_BLOCK
];
2456 ext3_free_branches(handle
, inode
, NULL
, &nr
, &nr
+1, 3);
2457 i_data
[EXT3_TIND_BLOCK
] = 0;
2459 case EXT3_TIND_BLOCK
:
2463 ext3_discard_reservation(inode
);
2465 mutex_unlock(&ei
->truncate_mutex
);
2466 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME_SEC
;
2467 ext3_mark_inode_dirty(handle
, inode
);
2470 * In a multi-transaction truncate, we only make the final transaction
2477 * If this was a simple ftruncate(), and the file will remain alive
2478 * then we need to clear up the orphan record which we created above.
2479 * However, if this was a real unlink then we were called by
2480 * ext3_delete_inode(), and we allow that function to clean up the
2481 * orphan info for us.
2484 ext3_orphan_del(handle
, inode
);
2486 ext3_journal_stop(handle
);
2489 static ext3_fsblk_t
ext3_get_inode_block(struct super_block
*sb
,
2490 unsigned long ino
, struct ext3_iloc
*iloc
)
2492 unsigned long block_group
;
2493 unsigned long offset
;
2495 struct ext3_group_desc
*gdp
;
2497 if (!ext3_valid_inum(sb
, ino
)) {
2499 * This error is already checked for in namei.c unless we are
2500 * looking at an NFS filehandle, in which case no error
2506 block_group
= (ino
- 1) / EXT3_INODES_PER_GROUP(sb
);
2507 gdp
= ext3_get_group_desc(sb
, block_group
, NULL
);
2511 * Figure out the offset within the block group inode table
2513 offset
= ((ino
- 1) % EXT3_INODES_PER_GROUP(sb
)) *
2514 EXT3_INODE_SIZE(sb
);
2515 block
= le32_to_cpu(gdp
->bg_inode_table
) +
2516 (offset
>> EXT3_BLOCK_SIZE_BITS(sb
));
2518 iloc
->block_group
= block_group
;
2519 iloc
->offset
= offset
& (EXT3_BLOCK_SIZE(sb
) - 1);
2524 * ext3_get_inode_loc returns with an extra refcount against the inode's
2525 * underlying buffer_head on success. If 'in_mem' is true, we have all
2526 * data in memory that is needed to recreate the on-disk version of this
2529 static int __ext3_get_inode_loc(struct inode
*inode
,
2530 struct ext3_iloc
*iloc
, int in_mem
)
2533 struct buffer_head
*bh
;
2535 block
= ext3_get_inode_block(inode
->i_sb
, inode
->i_ino
, iloc
);
2539 bh
= sb_getblk(inode
->i_sb
, block
);
2541 ext3_error (inode
->i_sb
, "ext3_get_inode_loc",
2542 "unable to read inode block - "
2543 "inode=%lu, block="E3FSBLK
,
2544 inode
->i_ino
, block
);
2547 if (!buffer_uptodate(bh
)) {
2551 * If the buffer has the write error flag, we have failed
2552 * to write out another inode in the same block. In this
2553 * case, we don't have to read the block because we may
2554 * read the old inode data successfully.
2556 if (buffer_write_io_error(bh
) && !buffer_uptodate(bh
))
2557 set_buffer_uptodate(bh
);
2559 if (buffer_uptodate(bh
)) {
2560 /* someone brought it uptodate while we waited */
2566 * If we have all information of the inode in memory and this
2567 * is the only valid inode in the block, we need not read the
2571 struct buffer_head
*bitmap_bh
;
2572 struct ext3_group_desc
*desc
;
2573 int inodes_per_buffer
;
2574 int inode_offset
, i
;
2578 block_group
= (inode
->i_ino
- 1) /
2579 EXT3_INODES_PER_GROUP(inode
->i_sb
);
2580 inodes_per_buffer
= bh
->b_size
/
2581 EXT3_INODE_SIZE(inode
->i_sb
);
2582 inode_offset
= ((inode
->i_ino
- 1) %
2583 EXT3_INODES_PER_GROUP(inode
->i_sb
));
2584 start
= inode_offset
& ~(inodes_per_buffer
- 1);
2586 /* Is the inode bitmap in cache? */
2587 desc
= ext3_get_group_desc(inode
->i_sb
,
2592 bitmap_bh
= sb_getblk(inode
->i_sb
,
2593 le32_to_cpu(desc
->bg_inode_bitmap
));
2598 * If the inode bitmap isn't in cache then the
2599 * optimisation may end up performing two reads instead
2600 * of one, so skip it.
2602 if (!buffer_uptodate(bitmap_bh
)) {
2606 for (i
= start
; i
< start
+ inodes_per_buffer
; i
++) {
2607 if (i
== inode_offset
)
2609 if (ext3_test_bit(i
, bitmap_bh
->b_data
))
2613 if (i
== start
+ inodes_per_buffer
) {
2614 /* all other inodes are free, so skip I/O */
2615 memset(bh
->b_data
, 0, bh
->b_size
);
2616 set_buffer_uptodate(bh
);
2624 * There are other valid inodes in the buffer, this inode
2625 * has in-inode xattrs, or we don't have this inode in memory.
2626 * Read the block from disk.
2629 bh
->b_end_io
= end_buffer_read_sync
;
2630 submit_bh(READ_META
, bh
);
2632 if (!buffer_uptodate(bh
)) {
2633 ext3_error(inode
->i_sb
, "ext3_get_inode_loc",
2634 "unable to read inode block - "
2635 "inode=%lu, block="E3FSBLK
,
2636 inode
->i_ino
, block
);
2646 int ext3_get_inode_loc(struct inode
*inode
, struct ext3_iloc
*iloc
)
2648 /* We have all inode data except xattrs in memory here. */
2649 return __ext3_get_inode_loc(inode
, iloc
,
2650 !(EXT3_I(inode
)->i_state
& EXT3_STATE_XATTR
));
2653 void ext3_set_inode_flags(struct inode
*inode
)
2655 unsigned int flags
= EXT3_I(inode
)->i_flags
;
2657 inode
->i_flags
&= ~(S_SYNC
|S_APPEND
|S_IMMUTABLE
|S_NOATIME
|S_DIRSYNC
);
2658 if (flags
& EXT3_SYNC_FL
)
2659 inode
->i_flags
|= S_SYNC
;
2660 if (flags
& EXT3_APPEND_FL
)
2661 inode
->i_flags
|= S_APPEND
;
2662 if (flags
& EXT3_IMMUTABLE_FL
)
2663 inode
->i_flags
|= S_IMMUTABLE
;
2664 if (flags
& EXT3_NOATIME_FL
)
2665 inode
->i_flags
|= S_NOATIME
;
2666 if (flags
& EXT3_DIRSYNC_FL
)
2667 inode
->i_flags
|= S_DIRSYNC
;
2670 /* Propagate flags from i_flags to EXT3_I(inode)->i_flags */
2671 void ext3_get_inode_flags(struct ext3_inode_info
*ei
)
2673 unsigned int flags
= ei
->vfs_inode
.i_flags
;
2675 ei
->i_flags
&= ~(EXT3_SYNC_FL
|EXT3_APPEND_FL
|
2676 EXT3_IMMUTABLE_FL
|EXT3_NOATIME_FL
|EXT3_DIRSYNC_FL
);
2678 ei
->i_flags
|= EXT3_SYNC_FL
;
2679 if (flags
& S_APPEND
)
2680 ei
->i_flags
|= EXT3_APPEND_FL
;
2681 if (flags
& S_IMMUTABLE
)
2682 ei
->i_flags
|= EXT3_IMMUTABLE_FL
;
2683 if (flags
& S_NOATIME
)
2684 ei
->i_flags
|= EXT3_NOATIME_FL
;
2685 if (flags
& S_DIRSYNC
)
2686 ei
->i_flags
|= EXT3_DIRSYNC_FL
;
2689 struct inode
*ext3_iget(struct super_block
*sb
, unsigned long ino
)
2691 struct ext3_iloc iloc
;
2692 struct ext3_inode
*raw_inode
;
2693 struct ext3_inode_info
*ei
;
2694 struct buffer_head
*bh
;
2695 struct inode
*inode
;
2699 inode
= iget_locked(sb
, ino
);
2701 return ERR_PTR(-ENOMEM
);
2702 if (!(inode
->i_state
& I_NEW
))
2706 #ifdef CONFIG_EXT3_FS_POSIX_ACL
2707 ei
->i_acl
= EXT3_ACL_NOT_CACHED
;
2708 ei
->i_default_acl
= EXT3_ACL_NOT_CACHED
;
2710 ei
->i_block_alloc_info
= NULL
;
2712 ret
= __ext3_get_inode_loc(inode
, &iloc
, 0);
2716 raw_inode
= ext3_raw_inode(&iloc
);
2717 inode
->i_mode
= le16_to_cpu(raw_inode
->i_mode
);
2718 inode
->i_uid
= (uid_t
)le16_to_cpu(raw_inode
->i_uid_low
);
2719 inode
->i_gid
= (gid_t
)le16_to_cpu(raw_inode
->i_gid_low
);
2720 if(!(test_opt (inode
->i_sb
, NO_UID32
))) {
2721 inode
->i_uid
|= le16_to_cpu(raw_inode
->i_uid_high
) << 16;
2722 inode
->i_gid
|= le16_to_cpu(raw_inode
->i_gid_high
) << 16;
2724 inode
->i_nlink
= le16_to_cpu(raw_inode
->i_links_count
);
2725 inode
->i_size
= le32_to_cpu(raw_inode
->i_size
);
2726 inode
->i_atime
.tv_sec
= (signed)le32_to_cpu(raw_inode
->i_atime
);
2727 inode
->i_ctime
.tv_sec
= (signed)le32_to_cpu(raw_inode
->i_ctime
);
2728 inode
->i_mtime
.tv_sec
= (signed)le32_to_cpu(raw_inode
->i_mtime
);
2729 inode
->i_atime
.tv_nsec
= inode
->i_ctime
.tv_nsec
= inode
->i_mtime
.tv_nsec
= 0;
2732 ei
->i_dir_start_lookup
= 0;
2733 ei
->i_dtime
= le32_to_cpu(raw_inode
->i_dtime
);
2734 /* We now have enough fields to check if the inode was active or not.
2735 * This is needed because nfsd might try to access dead inodes
2736 * the test is that same one that e2fsck uses
2737 * NeilBrown 1999oct15
2739 if (inode
->i_nlink
== 0) {
2740 if (inode
->i_mode
== 0 ||
2741 !(EXT3_SB(inode
->i_sb
)->s_mount_state
& EXT3_ORPHAN_FS
)) {
2742 /* this inode is deleted */
2747 /* The only unlinked inodes we let through here have
2748 * valid i_mode and are being read by the orphan
2749 * recovery code: that's fine, we're about to complete
2750 * the process of deleting those. */
2752 inode
->i_blocks
= le32_to_cpu(raw_inode
->i_blocks
);
2753 ei
->i_flags
= le32_to_cpu(raw_inode
->i_flags
);
2754 #ifdef EXT3_FRAGMENTS
2755 ei
->i_faddr
= le32_to_cpu(raw_inode
->i_faddr
);
2756 ei
->i_frag_no
= raw_inode
->i_frag
;
2757 ei
->i_frag_size
= raw_inode
->i_fsize
;
2759 ei
->i_file_acl
= le32_to_cpu(raw_inode
->i_file_acl
);
2760 if (!S_ISREG(inode
->i_mode
)) {
2761 ei
->i_dir_acl
= le32_to_cpu(raw_inode
->i_dir_acl
);
2764 ((__u64
)le32_to_cpu(raw_inode
->i_size_high
)) << 32;
2766 ei
->i_disksize
= inode
->i_size
;
2767 inode
->i_generation
= le32_to_cpu(raw_inode
->i_generation
);
2768 ei
->i_block_group
= iloc
.block_group
;
2770 * NOTE! The in-memory inode i_data array is in little-endian order
2771 * even on big-endian machines: we do NOT byteswap the block numbers!
2773 for (block
= 0; block
< EXT3_N_BLOCKS
; block
++)
2774 ei
->i_data
[block
] = raw_inode
->i_block
[block
];
2775 INIT_LIST_HEAD(&ei
->i_orphan
);
2777 if (inode
->i_ino
>= EXT3_FIRST_INO(inode
->i_sb
) + 1 &&
2778 EXT3_INODE_SIZE(inode
->i_sb
) > EXT3_GOOD_OLD_INODE_SIZE
) {
2780 * When mke2fs creates big inodes it does not zero out
2781 * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE,
2782 * so ignore those first few inodes.
2784 ei
->i_extra_isize
= le16_to_cpu(raw_inode
->i_extra_isize
);
2785 if (EXT3_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
>
2786 EXT3_INODE_SIZE(inode
->i_sb
)) {
2791 if (ei
->i_extra_isize
== 0) {
2792 /* The extra space is currently unused. Use it. */
2793 ei
->i_extra_isize
= sizeof(struct ext3_inode
) -
2794 EXT3_GOOD_OLD_INODE_SIZE
;
2796 __le32
*magic
= (void *)raw_inode
+
2797 EXT3_GOOD_OLD_INODE_SIZE
+
2799 if (*magic
== cpu_to_le32(EXT3_XATTR_MAGIC
))
2800 ei
->i_state
|= EXT3_STATE_XATTR
;
2803 ei
->i_extra_isize
= 0;
2805 if (S_ISREG(inode
->i_mode
)) {
2806 inode
->i_op
= &ext3_file_inode_operations
;
2807 inode
->i_fop
= &ext3_file_operations
;
2808 ext3_set_aops(inode
);
2809 } else if (S_ISDIR(inode
->i_mode
)) {
2810 inode
->i_op
= &ext3_dir_inode_operations
;
2811 inode
->i_fop
= &ext3_dir_operations
;
2812 } else if (S_ISLNK(inode
->i_mode
)) {
2813 if (ext3_inode_is_fast_symlink(inode
))
2814 inode
->i_op
= &ext3_fast_symlink_inode_operations
;
2816 inode
->i_op
= &ext3_symlink_inode_operations
;
2817 ext3_set_aops(inode
);
2820 inode
->i_op
= &ext3_special_inode_operations
;
2821 if (raw_inode
->i_block
[0])
2822 init_special_inode(inode
, inode
->i_mode
,
2823 old_decode_dev(le32_to_cpu(raw_inode
->i_block
[0])));
2825 init_special_inode(inode
, inode
->i_mode
,
2826 new_decode_dev(le32_to_cpu(raw_inode
->i_block
[1])));
2829 ext3_set_inode_flags(inode
);
2830 unlock_new_inode(inode
);
2835 return ERR_PTR(ret
);
2839 * Post the struct inode info into an on-disk inode location in the
2840 * buffer-cache. This gobbles the caller's reference to the
2841 * buffer_head in the inode location struct.
2843 * The caller must have write access to iloc->bh.
2845 static int ext3_do_update_inode(handle_t
*handle
,
2846 struct inode
*inode
,
2847 struct ext3_iloc
*iloc
)
2849 struct ext3_inode
*raw_inode
= ext3_raw_inode(iloc
);
2850 struct ext3_inode_info
*ei
= EXT3_I(inode
);
2851 struct buffer_head
*bh
= iloc
->bh
;
2852 int err
= 0, rc
, block
;
2854 /* For fields not not tracking in the in-memory inode,
2855 * initialise them to zero for new inodes. */
2856 if (ei
->i_state
& EXT3_STATE_NEW
)
2857 memset(raw_inode
, 0, EXT3_SB(inode
->i_sb
)->s_inode_size
);
2859 ext3_get_inode_flags(ei
);
2860 raw_inode
->i_mode
= cpu_to_le16(inode
->i_mode
);
2861 if(!(test_opt(inode
->i_sb
, NO_UID32
))) {
2862 raw_inode
->i_uid_low
= cpu_to_le16(low_16_bits(inode
->i_uid
));
2863 raw_inode
->i_gid_low
= cpu_to_le16(low_16_bits(inode
->i_gid
));
2865 * Fix up interoperability with old kernels. Otherwise, old inodes get
2866 * re-used with the upper 16 bits of the uid/gid intact
2869 raw_inode
->i_uid_high
=
2870 cpu_to_le16(high_16_bits(inode
->i_uid
));
2871 raw_inode
->i_gid_high
=
2872 cpu_to_le16(high_16_bits(inode
->i_gid
));
2874 raw_inode
->i_uid_high
= 0;
2875 raw_inode
->i_gid_high
= 0;
2878 raw_inode
->i_uid_low
=
2879 cpu_to_le16(fs_high2lowuid(inode
->i_uid
));
2880 raw_inode
->i_gid_low
=
2881 cpu_to_le16(fs_high2lowgid(inode
->i_gid
));
2882 raw_inode
->i_uid_high
= 0;
2883 raw_inode
->i_gid_high
= 0;
2885 raw_inode
->i_links_count
= cpu_to_le16(inode
->i_nlink
);
2886 raw_inode
->i_size
= cpu_to_le32(ei
->i_disksize
);
2887 raw_inode
->i_atime
= cpu_to_le32(inode
->i_atime
.tv_sec
);
2888 raw_inode
->i_ctime
= cpu_to_le32(inode
->i_ctime
.tv_sec
);
2889 raw_inode
->i_mtime
= cpu_to_le32(inode
->i_mtime
.tv_sec
);
2890 raw_inode
->i_blocks
= cpu_to_le32(inode
->i_blocks
);
2891 raw_inode
->i_dtime
= cpu_to_le32(ei
->i_dtime
);
2892 raw_inode
->i_flags
= cpu_to_le32(ei
->i_flags
);
2893 #ifdef EXT3_FRAGMENTS
2894 raw_inode
->i_faddr
= cpu_to_le32(ei
->i_faddr
);
2895 raw_inode
->i_frag
= ei
->i_frag_no
;
2896 raw_inode
->i_fsize
= ei
->i_frag_size
;
2898 raw_inode
->i_file_acl
= cpu_to_le32(ei
->i_file_acl
);
2899 if (!S_ISREG(inode
->i_mode
)) {
2900 raw_inode
->i_dir_acl
= cpu_to_le32(ei
->i_dir_acl
);
2902 raw_inode
->i_size_high
=
2903 cpu_to_le32(ei
->i_disksize
>> 32);
2904 if (ei
->i_disksize
> 0x7fffffffULL
) {
2905 struct super_block
*sb
= inode
->i_sb
;
2906 if (!EXT3_HAS_RO_COMPAT_FEATURE(sb
,
2907 EXT3_FEATURE_RO_COMPAT_LARGE_FILE
) ||
2908 EXT3_SB(sb
)->s_es
->s_rev_level
==
2909 cpu_to_le32(EXT3_GOOD_OLD_REV
)) {
2910 /* If this is the first large file
2911 * created, add a flag to the superblock.
2913 err
= ext3_journal_get_write_access(handle
,
2914 EXT3_SB(sb
)->s_sbh
);
2917 ext3_update_dynamic_rev(sb
);
2918 EXT3_SET_RO_COMPAT_FEATURE(sb
,
2919 EXT3_FEATURE_RO_COMPAT_LARGE_FILE
);
2922 err
= ext3_journal_dirty_metadata(handle
,
2923 EXT3_SB(sb
)->s_sbh
);
2927 raw_inode
->i_generation
= cpu_to_le32(inode
->i_generation
);
2928 if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
)) {
2929 if (old_valid_dev(inode
->i_rdev
)) {
2930 raw_inode
->i_block
[0] =
2931 cpu_to_le32(old_encode_dev(inode
->i_rdev
));
2932 raw_inode
->i_block
[1] = 0;
2934 raw_inode
->i_block
[0] = 0;
2935 raw_inode
->i_block
[1] =
2936 cpu_to_le32(new_encode_dev(inode
->i_rdev
));
2937 raw_inode
->i_block
[2] = 0;
2939 } else for (block
= 0; block
< EXT3_N_BLOCKS
; block
++)
2940 raw_inode
->i_block
[block
] = ei
->i_data
[block
];
2942 if (ei
->i_extra_isize
)
2943 raw_inode
->i_extra_isize
= cpu_to_le16(ei
->i_extra_isize
);
2945 BUFFER_TRACE(bh
, "call ext3_journal_dirty_metadata");
2946 rc
= ext3_journal_dirty_metadata(handle
, bh
);
2949 ei
->i_state
&= ~EXT3_STATE_NEW
;
2953 ext3_std_error(inode
->i_sb
, err
);
2958 * ext3_write_inode()
2960 * We are called from a few places:
2962 * - Within generic_file_write() for O_SYNC files.
2963 * Here, there will be no transaction running. We wait for any running
2964 * trasnaction to commit.
2966 * - Within sys_sync(), kupdate and such.
2967 * We wait on commit, if tol to.
2969 * - Within prune_icache() (PF_MEMALLOC == true)
2970 * Here we simply return. We can't afford to block kswapd on the
2973 * In all cases it is actually safe for us to return without doing anything,
2974 * because the inode has been copied into a raw inode buffer in
2975 * ext3_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
2978 * Note that we are absolutely dependent upon all inode dirtiers doing the
2979 * right thing: they *must* call mark_inode_dirty() after dirtying info in
2980 * which we are interested.
2982 * It would be a bug for them to not do this. The code:
2984 * mark_inode_dirty(inode)
2986 * inode->i_size = expr;
2988 * is in error because a kswapd-driven write_inode() could occur while
2989 * `stuff()' is running, and the new i_size will be lost. Plus the inode
2990 * will no longer be on the superblock's dirty inode list.
2992 int ext3_write_inode(struct inode
*inode
, int wait
)
2994 if (current
->flags
& PF_MEMALLOC
)
2997 if (ext3_journal_current_handle()) {
2998 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
3006 return ext3_force_commit(inode
->i_sb
);
3012 * Called from notify_change.
3014 * We want to trap VFS attempts to truncate the file as soon as
3015 * possible. In particular, we want to make sure that when the VFS
3016 * shrinks i_size, we put the inode on the orphan list and modify
3017 * i_disksize immediately, so that during the subsequent flushing of
3018 * dirty pages and freeing of disk blocks, we can guarantee that any
3019 * commit will leave the blocks being flushed in an unused state on
3020 * disk. (On recovery, the inode will get truncated and the blocks will
3021 * be freed, so we have a strong guarantee that no future commit will
3022 * leave these blocks visible to the user.)
3024 * Called with inode->sem down.
3026 int ext3_setattr(struct dentry
*dentry
, struct iattr
*attr
)
3028 struct inode
*inode
= dentry
->d_inode
;
3030 const unsigned int ia_valid
= attr
->ia_valid
;
3032 error
= inode_change_ok(inode
, attr
);
3036 if ((ia_valid
& ATTR_UID
&& attr
->ia_uid
!= inode
->i_uid
) ||
3037 (ia_valid
& ATTR_GID
&& attr
->ia_gid
!= inode
->i_gid
)) {
3040 /* (user+group)*(old+new) structure, inode write (sb,
3041 * inode block, ? - but truncate inode update has it) */
3042 handle
= ext3_journal_start(inode
, 2*(EXT3_QUOTA_INIT_BLOCKS(inode
->i_sb
)+
3043 EXT3_QUOTA_DEL_BLOCKS(inode
->i_sb
))+3);
3044 if (IS_ERR(handle
)) {
3045 error
= PTR_ERR(handle
);
3048 error
= DQUOT_TRANSFER(inode
, attr
) ? -EDQUOT
: 0;
3050 ext3_journal_stop(handle
);
3053 /* Update corresponding info in inode so that everything is in
3054 * one transaction */
3055 if (attr
->ia_valid
& ATTR_UID
)
3056 inode
->i_uid
= attr
->ia_uid
;
3057 if (attr
->ia_valid
& ATTR_GID
)
3058 inode
->i_gid
= attr
->ia_gid
;
3059 error
= ext3_mark_inode_dirty(handle
, inode
);
3060 ext3_journal_stop(handle
);
3063 if (S_ISREG(inode
->i_mode
) &&
3064 attr
->ia_valid
& ATTR_SIZE
&& attr
->ia_size
< inode
->i_size
) {
3067 handle
= ext3_journal_start(inode
, 3);
3068 if (IS_ERR(handle
)) {
3069 error
= PTR_ERR(handle
);
3073 error
= ext3_orphan_add(handle
, inode
);
3074 EXT3_I(inode
)->i_disksize
= attr
->ia_size
;
3075 rc
= ext3_mark_inode_dirty(handle
, inode
);
3078 ext3_journal_stop(handle
);
3081 rc
= inode_setattr(inode
, attr
);
3083 /* If inode_setattr's call to ext3_truncate failed to get a
3084 * transaction handle at all, we need to clean up the in-core
3085 * orphan list manually. */
3087 ext3_orphan_del(NULL
, inode
);
3089 if (!rc
&& (ia_valid
& ATTR_MODE
))
3090 rc
= ext3_acl_chmod(inode
);
3093 ext3_std_error(inode
->i_sb
, error
);
3101 * How many blocks doth make a writepage()?
3103 * With N blocks per page, it may be:
3108 * N+5 bitmap blocks (from the above)
3109 * N+5 group descriptor summary blocks
3112 * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quote files
3114 * 3 * (N + 5) + 2 + 2 * EXT3_SINGLEDATA_TRANS_BLOCKS
3116 * With ordered or writeback data it's the same, less the N data blocks.
3118 * If the inode's direct blocks can hold an integral number of pages then a
3119 * page cannot straddle two indirect blocks, and we can only touch one indirect
3120 * and dindirect block, and the "5" above becomes "3".
3122 * This still overestimates under most circumstances. If we were to pass the
3123 * start and end offsets in here as well we could do block_to_path() on each
3124 * block and work out the exact number of indirects which are touched. Pah.
3127 static int ext3_writepage_trans_blocks(struct inode
*inode
)
3129 int bpp
= ext3_journal_blocks_per_page(inode
);
3130 int indirects
= (EXT3_NDIR_BLOCKS
% bpp
) ? 5 : 3;
3133 if (ext3_should_journal_data(inode
))
3134 ret
= 3 * (bpp
+ indirects
) + 2;
3136 ret
= 2 * (bpp
+ indirects
) + 2;
3139 /* We know that structure was already allocated during DQUOT_INIT so
3140 * we will be updating only the data blocks + inodes */
3141 ret
+= 2*EXT3_QUOTA_TRANS_BLOCKS(inode
->i_sb
);
3148 * The caller must have previously called ext3_reserve_inode_write().
3149 * Give this, we know that the caller already has write access to iloc->bh.
3151 int ext3_mark_iloc_dirty(handle_t
*handle
,
3152 struct inode
*inode
, struct ext3_iloc
*iloc
)
3156 /* the do_update_inode consumes one bh->b_count */
3159 /* ext3_do_update_inode() does journal_dirty_metadata */
3160 err
= ext3_do_update_inode(handle
, inode
, iloc
);
3166 * On success, We end up with an outstanding reference count against
3167 * iloc->bh. This _must_ be cleaned up later.
3171 ext3_reserve_inode_write(handle_t
*handle
, struct inode
*inode
,
3172 struct ext3_iloc
*iloc
)
3176 err
= ext3_get_inode_loc(inode
, iloc
);
3178 BUFFER_TRACE(iloc
->bh
, "get_write_access");
3179 err
= ext3_journal_get_write_access(handle
, iloc
->bh
);
3186 ext3_std_error(inode
->i_sb
, err
);
3191 * What we do here is to mark the in-core inode as clean with respect to inode
3192 * dirtiness (it may still be data-dirty).
3193 * This means that the in-core inode may be reaped by prune_icache
3194 * without having to perform any I/O. This is a very good thing,
3195 * because *any* task may call prune_icache - even ones which
3196 * have a transaction open against a different journal.
3198 * Is this cheating? Not really. Sure, we haven't written the
3199 * inode out, but prune_icache isn't a user-visible syncing function.
3200 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
3201 * we start and wait on commits.
3203 * Is this efficient/effective? Well, we're being nice to the system
3204 * by cleaning up our inodes proactively so they can be reaped
3205 * without I/O. But we are potentially leaving up to five seconds'
3206 * worth of inodes floating about which prune_icache wants us to
3207 * write out. One way to fix that would be to get prune_icache()
3208 * to do a write_super() to free up some memory. It has the desired
3211 int ext3_mark_inode_dirty(handle_t
*handle
, struct inode
*inode
)
3213 struct ext3_iloc iloc
;
3217 err
= ext3_reserve_inode_write(handle
, inode
, &iloc
);
3219 err
= ext3_mark_iloc_dirty(handle
, inode
, &iloc
);
3224 * ext3_dirty_inode() is called from __mark_inode_dirty()
3226 * We're really interested in the case where a file is being extended.
3227 * i_size has been changed by generic_commit_write() and we thus need
3228 * to include the updated inode in the current transaction.
3230 * Also, DQUOT_ALLOC_SPACE() will always dirty the inode when blocks
3231 * are allocated to the file.
3233 * If the inode is marked synchronous, we don't honour that here - doing
3234 * so would cause a commit on atime updates, which we don't bother doing.
3235 * We handle synchronous inodes at the highest possible level.
3237 void ext3_dirty_inode(struct inode
*inode
)
3239 handle_t
*current_handle
= ext3_journal_current_handle();
3242 handle
= ext3_journal_start(inode
, 2);
3245 if (current_handle
&&
3246 current_handle
->h_transaction
!= handle
->h_transaction
) {
3247 /* This task has a transaction open against a different fs */
3248 printk(KERN_EMERG
"%s: transactions do not match!\n",
3251 jbd_debug(5, "marking dirty. outer handle=%p\n",
3253 ext3_mark_inode_dirty(handle
, inode
);
3255 ext3_journal_stop(handle
);
3262 * Bind an inode's backing buffer_head into this transaction, to prevent
3263 * it from being flushed to disk early. Unlike
3264 * ext3_reserve_inode_write, this leaves behind no bh reference and
3265 * returns no iloc structure, so the caller needs to repeat the iloc
3266 * lookup to mark the inode dirty later.
3268 static int ext3_pin_inode(handle_t
*handle
, struct inode
*inode
)
3270 struct ext3_iloc iloc
;
3274 err
= ext3_get_inode_loc(inode
, &iloc
);
3276 BUFFER_TRACE(iloc
.bh
, "get_write_access");
3277 err
= journal_get_write_access(handle
, iloc
.bh
);
3279 err
= ext3_journal_dirty_metadata(handle
,
3284 ext3_std_error(inode
->i_sb
, err
);
3289 int ext3_change_inode_journal_flag(struct inode
*inode
, int val
)
3296 * We have to be very careful here: changing a data block's
3297 * journaling status dynamically is dangerous. If we write a
3298 * data block to the journal, change the status and then delete
3299 * that block, we risk forgetting to revoke the old log record
3300 * from the journal and so a subsequent replay can corrupt data.
3301 * So, first we make sure that the journal is empty and that
3302 * nobody is changing anything.
3305 journal
= EXT3_JOURNAL(inode
);
3306 if (is_journal_aborted(journal
))
3309 journal_lock_updates(journal
);
3310 journal_flush(journal
);
3313 * OK, there are no updates running now, and all cached data is
3314 * synced to disk. We are now in a completely consistent state
3315 * which doesn't have anything in the journal, and we know that
3316 * no filesystem updates are running, so it is safe to modify
3317 * the inode's in-core data-journaling state flag now.
3321 EXT3_I(inode
)->i_flags
|= EXT3_JOURNAL_DATA_FL
;
3323 EXT3_I(inode
)->i_flags
&= ~EXT3_JOURNAL_DATA_FL
;
3324 ext3_set_aops(inode
);
3326 journal_unlock_updates(journal
);
3328 /* Finally we can mark the inode as dirty. */
3330 handle
= ext3_journal_start(inode
, 1);
3332 return PTR_ERR(handle
);
3334 err
= ext3_mark_inode_dirty(handle
, inode
);
3336 ext3_journal_stop(handle
);
3337 ext3_std_error(inode
->i_sb
, err
);