2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 #include "xfs_types.h"
22 #include "xfs_trans.h"
25 #include "xfs_mount.h"
26 #include "xfs_da_btree.h"
27 #include "xfs_bmap_btree.h"
28 #include "xfs_dinode.h"
29 #include "xfs_inode.h"
30 #include "xfs_dir2_format.h"
31 #include "xfs_dir2_priv.h"
32 #include "xfs_error.h"
34 STATIC xfs_dir2_data_free_t
*
35 xfs_dir2_data_freefind(xfs_dir2_data_hdr_t
*hdr
, xfs_dir2_data_unused_t
*dup
);
38 * Check the consistency of the data block.
39 * The input can also be a block-format directory.
40 * Return 0 is the buffer is good, otherwise an error.
43 __xfs_dir2_data_check(
44 struct xfs_inode
*dp
, /* incore inode pointer */
45 struct xfs_buf
*bp
) /* data block's buffer */
47 xfs_dir2_dataptr_t addr
; /* addr for leaf lookup */
48 xfs_dir2_data_free_t
*bf
; /* bestfree table */
49 xfs_dir2_block_tail_t
*btp
=NULL
; /* block tail */
50 int count
; /* count of entries found */
51 xfs_dir2_data_hdr_t
*hdr
; /* data block header */
52 xfs_dir2_data_entry_t
*dep
; /* data entry */
53 xfs_dir2_data_free_t
*dfp
; /* bestfree entry */
54 xfs_dir2_data_unused_t
*dup
; /* unused entry */
55 char *endp
; /* end of useful data */
56 int freeseen
; /* mask of bestfrees seen */
57 xfs_dahash_t hash
; /* hash of current name */
58 int i
; /* leaf index */
59 int lastfree
; /* last entry was unused */
60 xfs_dir2_leaf_entry_t
*lep
=NULL
; /* block leaf entries */
61 xfs_mount_t
*mp
; /* filesystem mount point */
62 char *p
; /* current data position */
63 int stale
; /* count of stale leaves */
66 mp
= bp
->b_target
->bt_mount
;
69 p
= (char *)(hdr
+ 1);
72 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
):
73 btp
= xfs_dir2_block_tail_p(mp
, hdr
);
74 lep
= xfs_dir2_block_leaf_p(btp
);
77 case cpu_to_be32(XFS_DIR2_DATA_MAGIC
):
78 endp
= (char *)hdr
+ mp
->m_dirblksize
;
81 XFS_ERROR_REPORT("Bad Magic", XFS_ERRLEVEL_LOW
, mp
);
85 count
= lastfree
= freeseen
= 0;
87 * Account for zero bestfree entries.
90 XFS_WANT_CORRUPTED_RETURN(!bf
[0].offset
);
94 XFS_WANT_CORRUPTED_RETURN(!bf
[1].offset
);
98 XFS_WANT_CORRUPTED_RETURN(!bf
[2].offset
);
102 XFS_WANT_CORRUPTED_RETURN(be16_to_cpu(bf
[0].length
) >=
103 be16_to_cpu(bf
[1].length
));
104 XFS_WANT_CORRUPTED_RETURN(be16_to_cpu(bf
[1].length
) >=
105 be16_to_cpu(bf
[2].length
));
107 * Loop over the data/unused entries.
110 dup
= (xfs_dir2_data_unused_t
*)p
;
112 * If it's unused, look for the space in the bestfree table.
113 * If we find it, account for that, else make sure it
114 * doesn't need to be there.
116 if (be16_to_cpu(dup
->freetag
) == XFS_DIR2_DATA_FREE_TAG
) {
117 XFS_WANT_CORRUPTED_RETURN(lastfree
== 0);
118 XFS_WANT_CORRUPTED_RETURN(
119 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup
)) ==
120 (char *)dup
- (char *)hdr
);
121 dfp
= xfs_dir2_data_freefind(hdr
, dup
);
124 XFS_WANT_CORRUPTED_RETURN(
125 (freeseen
& (1 << i
)) == 0);
128 XFS_WANT_CORRUPTED_RETURN(
129 be16_to_cpu(dup
->length
) <=
130 be16_to_cpu(bf
[2].length
));
132 p
+= be16_to_cpu(dup
->length
);
137 * It's a real entry. Validate the fields.
138 * If this is a block directory then make sure it's
139 * in the leaf section of the block.
140 * The linear search is crude but this is DEBUG code.
142 dep
= (xfs_dir2_data_entry_t
*)p
;
143 XFS_WANT_CORRUPTED_RETURN(dep
->namelen
!= 0);
144 XFS_WANT_CORRUPTED_RETURN(
145 !xfs_dir_ino_validate(mp
, be64_to_cpu(dep
->inumber
)));
146 XFS_WANT_CORRUPTED_RETURN(
147 be16_to_cpu(*xfs_dir2_data_entry_tag_p(dep
)) ==
148 (char *)dep
- (char *)hdr
);
151 if (hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
)) {
152 addr
= xfs_dir2_db_off_to_dataptr(mp
, mp
->m_dirdatablk
,
153 (xfs_dir2_data_aoff_t
)
154 ((char *)dep
- (char *)hdr
));
155 name
.name
= dep
->name
;
156 name
.len
= dep
->namelen
;
157 hash
= mp
->m_dirnameops
->hashname(&name
);
158 for (i
= 0; i
< be32_to_cpu(btp
->count
); i
++) {
159 if (be32_to_cpu(lep
[i
].address
) == addr
&&
160 be32_to_cpu(lep
[i
].hashval
) == hash
)
163 XFS_WANT_CORRUPTED_RETURN(i
< be32_to_cpu(btp
->count
));
165 p
+= xfs_dir2_data_entsize(dep
->namelen
);
168 * Need to have seen all the entries and all the bestfree slots.
170 XFS_WANT_CORRUPTED_RETURN(freeseen
== 7);
171 if (hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
)) {
172 for (i
= stale
= 0; i
< be32_to_cpu(btp
->count
); i
++) {
173 if (lep
[i
].address
==
174 cpu_to_be32(XFS_DIR2_NULL_DATAPTR
))
177 XFS_WANT_CORRUPTED_RETURN(
178 be32_to_cpu(lep
[i
].hashval
) >=
179 be32_to_cpu(lep
[i
- 1].hashval
));
181 XFS_WANT_CORRUPTED_RETURN(count
==
182 be32_to_cpu(btp
->count
) - be32_to_cpu(btp
->stale
));
183 XFS_WANT_CORRUPTED_RETURN(stale
== be32_to_cpu(btp
->stale
));
189 xfs_dir2_data_verify(
192 struct xfs_mount
*mp
= bp
->b_target
->bt_mount
;
193 struct xfs_dir2_data_hdr
*hdr
= bp
->b_addr
;
196 block_ok
= hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
);
197 block_ok
= block_ok
&& __xfs_dir2_data_check(NULL
, bp
) == 0;
200 XFS_CORRUPTION_ERROR(__func__
, XFS_ERRLEVEL_LOW
, mp
, hdr
);
201 xfs_buf_ioerror(bp
, EFSCORRUPTED
);
206 * Readahead of the first block of the directory when it is opened is completely
207 * oblivious to the format of the directory. Hence we can either get a block
208 * format buffer or a data format buffer on readahead.
211 xfs_dir2_data_reada_verify(
214 struct xfs_mount
*mp
= bp
->b_target
->bt_mount
;
215 struct xfs_dir2_data_hdr
*hdr
= bp
->b_addr
;
217 switch (hdr
->magic
) {
218 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
):
219 bp
->b_ops
= &xfs_dir2_block_buf_ops
;
220 bp
->b_ops
->verify_read(bp
);
222 case cpu_to_be32(XFS_DIR2_DATA_MAGIC
):
223 xfs_dir2_data_verify(bp
);
226 XFS_CORRUPTION_ERROR(__func__
, XFS_ERRLEVEL_LOW
, mp
, hdr
);
227 xfs_buf_ioerror(bp
, EFSCORRUPTED
);
233 xfs_dir2_data_read_verify(
236 xfs_dir2_data_verify(bp
);
240 xfs_dir2_data_write_verify(
243 xfs_dir2_data_verify(bp
);
246 const struct xfs_buf_ops xfs_dir2_data_buf_ops
= {
247 .verify_read
= xfs_dir2_data_read_verify
,
248 .verify_write
= xfs_dir2_data_write_verify
,
251 static const struct xfs_buf_ops xfs_dir2_data_reada_buf_ops
= {
252 .verify_read
= xfs_dir2_data_reada_verify
,
253 .verify_write
= xfs_dir2_data_write_verify
,
259 struct xfs_trans
*tp
,
260 struct xfs_inode
*dp
,
262 xfs_daddr_t mapped_bno
,
263 struct xfs_buf
**bpp
)
265 return xfs_da_read_buf(tp
, dp
, bno
, mapped_bno
, bpp
,
266 XFS_DATA_FORK
, &xfs_dir2_data_buf_ops
);
270 xfs_dir2_data_readahead(
271 struct xfs_trans
*tp
,
272 struct xfs_inode
*dp
,
274 xfs_daddr_t mapped_bno
)
276 return xfs_da_reada_buf(tp
, dp
, bno
, mapped_bno
,
277 XFS_DATA_FORK
, &xfs_dir2_data_reada_buf_ops
);
281 * Given a data block and an unused entry from that block,
282 * return the bestfree entry if any that corresponds to it.
284 STATIC xfs_dir2_data_free_t
*
285 xfs_dir2_data_freefind(
286 xfs_dir2_data_hdr_t
*hdr
, /* data block */
287 xfs_dir2_data_unused_t
*dup
) /* data unused entry */
289 xfs_dir2_data_free_t
*dfp
; /* bestfree entry */
290 xfs_dir2_data_aoff_t off
; /* offset value needed */
291 #if defined(DEBUG) && defined(__KERNEL__)
292 int matched
; /* matched the value */
293 int seenzero
; /* saw a 0 bestfree entry */
296 off
= (xfs_dir2_data_aoff_t
)((char *)dup
- (char *)hdr
);
297 #if defined(DEBUG) && defined(__KERNEL__)
299 * Validate some consistency in the bestfree table.
300 * Check order, non-overlapping entries, and if we find the
301 * one we're looking for it has to be exact.
303 ASSERT(hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
) ||
304 hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
));
305 for (dfp
= &hdr
->bestfree
[0], seenzero
= matched
= 0;
306 dfp
< &hdr
->bestfree
[XFS_DIR2_DATA_FD_COUNT
];
309 ASSERT(!dfp
->length
);
313 ASSERT(seenzero
== 0);
314 if (be16_to_cpu(dfp
->offset
) == off
) {
316 ASSERT(dfp
->length
== dup
->length
);
317 } else if (off
< be16_to_cpu(dfp
->offset
))
318 ASSERT(off
+ be16_to_cpu(dup
->length
) <= be16_to_cpu(dfp
->offset
));
320 ASSERT(be16_to_cpu(dfp
->offset
) + be16_to_cpu(dfp
->length
) <= off
);
321 ASSERT(matched
|| be16_to_cpu(dfp
->length
) >= be16_to_cpu(dup
->length
));
322 if (dfp
> &hdr
->bestfree
[0])
323 ASSERT(be16_to_cpu(dfp
[-1].length
) >= be16_to_cpu(dfp
[0].length
));
327 * If this is smaller than the smallest bestfree entry,
328 * it can't be there since they're sorted.
330 if (be16_to_cpu(dup
->length
) <
331 be16_to_cpu(hdr
->bestfree
[XFS_DIR2_DATA_FD_COUNT
- 1].length
))
334 * Look at the three bestfree entries for our guy.
336 for (dfp
= &hdr
->bestfree
[0];
337 dfp
< &hdr
->bestfree
[XFS_DIR2_DATA_FD_COUNT
];
341 if (be16_to_cpu(dfp
->offset
) == off
)
345 * Didn't find it. This only happens if there are duplicate lengths.
351 * Insert an unused-space entry into the bestfree table.
353 xfs_dir2_data_free_t
* /* entry inserted */
354 xfs_dir2_data_freeinsert(
355 xfs_dir2_data_hdr_t
*hdr
, /* data block pointer */
356 xfs_dir2_data_unused_t
*dup
, /* unused space */
357 int *loghead
) /* log the data header (out) */
359 xfs_dir2_data_free_t
*dfp
; /* bestfree table pointer */
360 xfs_dir2_data_free_t
new; /* new bestfree entry */
363 ASSERT(hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
) ||
364 hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
));
367 new.length
= dup
->length
;
368 new.offset
= cpu_to_be16((char *)dup
- (char *)hdr
);
371 * Insert at position 0, 1, or 2; or not at all.
373 if (be16_to_cpu(new.length
) > be16_to_cpu(dfp
[0].length
)) {
380 if (be16_to_cpu(new.length
) > be16_to_cpu(dfp
[1].length
)) {
386 if (be16_to_cpu(new.length
) > be16_to_cpu(dfp
[2].length
)) {
395 * Remove a bestfree entry from the table.
398 xfs_dir2_data_freeremove(
399 xfs_dir2_data_hdr_t
*hdr
, /* data block header */
400 xfs_dir2_data_free_t
*dfp
, /* bestfree entry pointer */
401 int *loghead
) /* out: log data header */
404 ASSERT(hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
) ||
405 hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
));
408 * It's the first entry, slide the next 2 up.
410 if (dfp
== &hdr
->bestfree
[0]) {
411 hdr
->bestfree
[0] = hdr
->bestfree
[1];
412 hdr
->bestfree
[1] = hdr
->bestfree
[2];
415 * It's the second entry, slide the 3rd entry up.
417 else if (dfp
== &hdr
->bestfree
[1])
418 hdr
->bestfree
[1] = hdr
->bestfree
[2];
420 * Must be the last entry.
423 ASSERT(dfp
== &hdr
->bestfree
[2]);
425 * Clear the 3rd entry, must be zero now.
427 hdr
->bestfree
[2].length
= 0;
428 hdr
->bestfree
[2].offset
= 0;
433 * Given a data block, reconstruct its bestfree map.
436 xfs_dir2_data_freescan(
437 xfs_mount_t
*mp
, /* filesystem mount point */
438 xfs_dir2_data_hdr_t
*hdr
, /* data block header */
439 int *loghead
) /* out: log data header */
441 xfs_dir2_block_tail_t
*btp
; /* block tail */
442 xfs_dir2_data_entry_t
*dep
; /* active data entry */
443 xfs_dir2_data_unused_t
*dup
; /* unused data entry */
444 char *endp
; /* end of block's data */
445 char *p
; /* current entry pointer */
448 ASSERT(hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
) ||
449 hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
));
452 * Start by clearing the table.
454 memset(hdr
->bestfree
, 0, sizeof(hdr
->bestfree
));
459 p
= (char *)(hdr
+ 1);
460 if (hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
)) {
461 btp
= xfs_dir2_block_tail_p(mp
, hdr
);
462 endp
= (char *)xfs_dir2_block_leaf_p(btp
);
464 endp
= (char *)hdr
+ mp
->m_dirblksize
;
466 * Loop over the block's entries.
469 dup
= (xfs_dir2_data_unused_t
*)p
;
471 * If it's a free entry, insert it.
473 if (be16_to_cpu(dup
->freetag
) == XFS_DIR2_DATA_FREE_TAG
) {
474 ASSERT((char *)dup
- (char *)hdr
==
475 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup
)));
476 xfs_dir2_data_freeinsert(hdr
, dup
, loghead
);
477 p
+= be16_to_cpu(dup
->length
);
480 * For active entries, check their tags and skip them.
483 dep
= (xfs_dir2_data_entry_t
*)p
;
484 ASSERT((char *)dep
- (char *)hdr
==
485 be16_to_cpu(*xfs_dir2_data_entry_tag_p(dep
)));
486 p
+= xfs_dir2_data_entsize(dep
->namelen
);
492 * Initialize a data block at the given block number in the directory.
493 * Give back the buffer for the created block.
497 xfs_da_args_t
*args
, /* directory operation args */
498 xfs_dir2_db_t blkno
, /* logical dir block number */
499 struct xfs_buf
**bpp
) /* output block buffer */
501 struct xfs_buf
*bp
; /* block buffer */
502 xfs_dir2_data_hdr_t
*hdr
; /* data block header */
503 xfs_inode_t
*dp
; /* incore directory inode */
504 xfs_dir2_data_unused_t
*dup
; /* unused entry pointer */
505 int error
; /* error return value */
506 int i
; /* bestfree index */
507 xfs_mount_t
*mp
; /* filesystem mount point */
508 xfs_trans_t
*tp
; /* transaction pointer */
515 * Get the buffer set up for the block.
517 error
= xfs_da_get_buf(tp
, dp
, xfs_dir2_db_to_da(mp
, blkno
), -1, &bp
,
521 bp
->b_ops
= &xfs_dir2_data_buf_ops
;
524 * Initialize the header.
527 hdr
->magic
= cpu_to_be32(XFS_DIR2_DATA_MAGIC
);
528 hdr
->bestfree
[0].offset
= cpu_to_be16(sizeof(*hdr
));
529 for (i
= 1; i
< XFS_DIR2_DATA_FD_COUNT
; i
++) {
530 hdr
->bestfree
[i
].length
= 0;
531 hdr
->bestfree
[i
].offset
= 0;
535 * Set up an unused entry for the block's body.
537 dup
= (xfs_dir2_data_unused_t
*)(hdr
+ 1);
538 dup
->freetag
= cpu_to_be16(XFS_DIR2_DATA_FREE_TAG
);
540 t
= mp
->m_dirblksize
- (uint
)sizeof(*hdr
);
541 hdr
->bestfree
[0].length
= cpu_to_be16(t
);
542 dup
->length
= cpu_to_be16(t
);
543 *xfs_dir2_data_unused_tag_p(dup
) = cpu_to_be16((char *)dup
- (char *)hdr
);
545 * Log it and return it.
547 xfs_dir2_data_log_header(tp
, bp
);
548 xfs_dir2_data_log_unused(tp
, bp
, dup
);
554 * Log an active data entry from the block.
557 xfs_dir2_data_log_entry(
558 struct xfs_trans
*tp
,
560 xfs_dir2_data_entry_t
*dep
) /* data entry pointer */
562 xfs_dir2_data_hdr_t
*hdr
= bp
->b_addr
;
564 ASSERT(hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
) ||
565 hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
));
567 xfs_trans_log_buf(tp
, bp
, (uint
)((char *)dep
- (char *)hdr
),
568 (uint
)((char *)(xfs_dir2_data_entry_tag_p(dep
) + 1) -
573 * Log a data block header.
576 xfs_dir2_data_log_header(
577 struct xfs_trans
*tp
,
580 xfs_dir2_data_hdr_t
*hdr
= bp
->b_addr
;
582 ASSERT(hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
) ||
583 hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
));
585 xfs_trans_log_buf(tp
, bp
, 0, sizeof(*hdr
) - 1);
589 * Log a data unused entry.
592 xfs_dir2_data_log_unused(
593 struct xfs_trans
*tp
,
595 xfs_dir2_data_unused_t
*dup
) /* data unused pointer */
597 xfs_dir2_data_hdr_t
*hdr
= bp
->b_addr
;
599 ASSERT(hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
) ||
600 hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
));
603 * Log the first part of the unused entry.
605 xfs_trans_log_buf(tp
, bp
, (uint
)((char *)dup
- (char *)hdr
),
606 (uint
)((char *)&dup
->length
+ sizeof(dup
->length
) -
609 * Log the end (tag) of the unused entry.
611 xfs_trans_log_buf(tp
, bp
,
612 (uint
)((char *)xfs_dir2_data_unused_tag_p(dup
) - (char *)hdr
),
613 (uint
)((char *)xfs_dir2_data_unused_tag_p(dup
) - (char *)hdr
+
614 sizeof(xfs_dir2_data_off_t
) - 1));
618 * Make a byte range in the data block unused.
619 * Its current contents are unimportant.
622 xfs_dir2_data_make_free(
623 struct xfs_trans
*tp
,
625 xfs_dir2_data_aoff_t offset
, /* starting byte offset */
626 xfs_dir2_data_aoff_t len
, /* length in bytes */
627 int *needlogp
, /* out: log header */
628 int *needscanp
) /* out: regen bestfree */
630 xfs_dir2_data_hdr_t
*hdr
; /* data block pointer */
631 xfs_dir2_data_free_t
*dfp
; /* bestfree pointer */
632 char *endptr
; /* end of data area */
633 xfs_mount_t
*mp
; /* filesystem mount point */
634 int needscan
; /* need to regen bestfree */
635 xfs_dir2_data_unused_t
*newdup
; /* new unused entry */
636 xfs_dir2_data_unused_t
*postdup
; /* unused entry after us */
637 xfs_dir2_data_unused_t
*prevdup
; /* unused entry before us */
643 * Figure out where the end of the data area is.
645 if (hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
))
646 endptr
= (char *)hdr
+ mp
->m_dirblksize
;
648 xfs_dir2_block_tail_t
*btp
; /* block tail */
650 ASSERT(hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
));
651 btp
= xfs_dir2_block_tail_p(mp
, hdr
);
652 endptr
= (char *)xfs_dir2_block_leaf_p(btp
);
655 * If this isn't the start of the block, then back up to
656 * the previous entry and see if it's free.
658 if (offset
> sizeof(*hdr
)) {
659 __be16
*tagp
; /* tag just before us */
661 tagp
= (__be16
*)((char *)hdr
+ offset
) - 1;
662 prevdup
= (xfs_dir2_data_unused_t
*)((char *)hdr
+ be16_to_cpu(*tagp
));
663 if (be16_to_cpu(prevdup
->freetag
) != XFS_DIR2_DATA_FREE_TAG
)
668 * If this isn't the end of the block, see if the entry after
671 if ((char *)hdr
+ offset
+ len
< endptr
) {
673 (xfs_dir2_data_unused_t
*)((char *)hdr
+ offset
+ len
);
674 if (be16_to_cpu(postdup
->freetag
) != XFS_DIR2_DATA_FREE_TAG
)
678 ASSERT(*needscanp
== 0);
681 * Previous and following entries are both free,
682 * merge everything into a single free entry.
684 if (prevdup
&& postdup
) {
685 xfs_dir2_data_free_t
*dfp2
; /* another bestfree pointer */
688 * See if prevdup and/or postdup are in bestfree table.
690 dfp
= xfs_dir2_data_freefind(hdr
, prevdup
);
691 dfp2
= xfs_dir2_data_freefind(hdr
, postdup
);
693 * We need a rescan unless there are exactly 2 free entries
694 * namely our two. Then we know what's happening, otherwise
695 * since the third bestfree is there, there might be more
698 needscan
= (hdr
->bestfree
[2].length
!= 0);
700 * Fix up the new big freespace.
702 be16_add_cpu(&prevdup
->length
, len
+ be16_to_cpu(postdup
->length
));
703 *xfs_dir2_data_unused_tag_p(prevdup
) =
704 cpu_to_be16((char *)prevdup
- (char *)hdr
);
705 xfs_dir2_data_log_unused(tp
, bp
, prevdup
);
708 * Has to be the case that entries 0 and 1 are
709 * dfp and dfp2 (don't know which is which), and
711 * Remove entry 1 first then entry 0.
714 if (dfp
== &hdr
->bestfree
[1]) {
715 dfp
= &hdr
->bestfree
[0];
717 dfp2
= &hdr
->bestfree
[1];
719 xfs_dir2_data_freeremove(hdr
, dfp2
, needlogp
);
720 xfs_dir2_data_freeremove(hdr
, dfp
, needlogp
);
722 * Now insert the new entry.
724 dfp
= xfs_dir2_data_freeinsert(hdr
, prevdup
, needlogp
);
725 ASSERT(dfp
== &hdr
->bestfree
[0]);
726 ASSERT(dfp
->length
== prevdup
->length
);
727 ASSERT(!dfp
[1].length
);
728 ASSERT(!dfp
[2].length
);
732 * The entry before us is free, merge with it.
735 dfp
= xfs_dir2_data_freefind(hdr
, prevdup
);
736 be16_add_cpu(&prevdup
->length
, len
);
737 *xfs_dir2_data_unused_tag_p(prevdup
) =
738 cpu_to_be16((char *)prevdup
- (char *)hdr
);
739 xfs_dir2_data_log_unused(tp
, bp
, prevdup
);
741 * If the previous entry was in the table, the new entry
742 * is longer, so it will be in the table too. Remove
743 * the old one and add the new one.
746 xfs_dir2_data_freeremove(hdr
, dfp
, needlogp
);
747 xfs_dir2_data_freeinsert(hdr
, prevdup
, needlogp
);
750 * Otherwise we need a scan if the new entry is big enough.
753 needscan
= be16_to_cpu(prevdup
->length
) >
754 be16_to_cpu(hdr
->bestfree
[2].length
);
758 * The following entry is free, merge with it.
761 dfp
= xfs_dir2_data_freefind(hdr
, postdup
);
762 newdup
= (xfs_dir2_data_unused_t
*)((char *)hdr
+ offset
);
763 newdup
->freetag
= cpu_to_be16(XFS_DIR2_DATA_FREE_TAG
);
764 newdup
->length
= cpu_to_be16(len
+ be16_to_cpu(postdup
->length
));
765 *xfs_dir2_data_unused_tag_p(newdup
) =
766 cpu_to_be16((char *)newdup
- (char *)hdr
);
767 xfs_dir2_data_log_unused(tp
, bp
, newdup
);
769 * If the following entry was in the table, the new entry
770 * is longer, so it will be in the table too. Remove
771 * the old one and add the new one.
774 xfs_dir2_data_freeremove(hdr
, dfp
, needlogp
);
775 xfs_dir2_data_freeinsert(hdr
, newdup
, needlogp
);
778 * Otherwise we need a scan if the new entry is big enough.
781 needscan
= be16_to_cpu(newdup
->length
) >
782 be16_to_cpu(hdr
->bestfree
[2].length
);
786 * Neither neighbor is free. Make a new entry.
789 newdup
= (xfs_dir2_data_unused_t
*)((char *)hdr
+ offset
);
790 newdup
->freetag
= cpu_to_be16(XFS_DIR2_DATA_FREE_TAG
);
791 newdup
->length
= cpu_to_be16(len
);
792 *xfs_dir2_data_unused_tag_p(newdup
) =
793 cpu_to_be16((char *)newdup
- (char *)hdr
);
794 xfs_dir2_data_log_unused(tp
, bp
, newdup
);
795 xfs_dir2_data_freeinsert(hdr
, newdup
, needlogp
);
797 *needscanp
= needscan
;
801 * Take a byte range out of an existing unused space and make it un-free.
804 xfs_dir2_data_use_free(
805 struct xfs_trans
*tp
,
807 xfs_dir2_data_unused_t
*dup
, /* unused entry */
808 xfs_dir2_data_aoff_t offset
, /* starting offset to use */
809 xfs_dir2_data_aoff_t len
, /* length to use */
810 int *needlogp
, /* out: need to log header */
811 int *needscanp
) /* out: need regen bestfree */
813 xfs_dir2_data_hdr_t
*hdr
; /* data block header */
814 xfs_dir2_data_free_t
*dfp
; /* bestfree pointer */
815 int matchback
; /* matches end of freespace */
816 int matchfront
; /* matches start of freespace */
817 int needscan
; /* need to regen bestfree */
818 xfs_dir2_data_unused_t
*newdup
; /* new unused entry */
819 xfs_dir2_data_unused_t
*newdup2
; /* another new unused entry */
820 int oldlen
; /* old unused entry's length */
823 ASSERT(hdr
->magic
== cpu_to_be32(XFS_DIR2_DATA_MAGIC
) ||
824 hdr
->magic
== cpu_to_be32(XFS_DIR2_BLOCK_MAGIC
));
825 ASSERT(be16_to_cpu(dup
->freetag
) == XFS_DIR2_DATA_FREE_TAG
);
826 ASSERT(offset
>= (char *)dup
- (char *)hdr
);
827 ASSERT(offset
+ len
<= (char *)dup
+ be16_to_cpu(dup
->length
) - (char *)hdr
);
828 ASSERT((char *)dup
- (char *)hdr
== be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup
)));
830 * Look up the entry in the bestfree table.
832 dfp
= xfs_dir2_data_freefind(hdr
, dup
);
833 oldlen
= be16_to_cpu(dup
->length
);
834 ASSERT(dfp
|| oldlen
<= be16_to_cpu(hdr
->bestfree
[2].length
));
836 * Check for alignment with front and back of the entry.
838 matchfront
= (char *)dup
- (char *)hdr
== offset
;
839 matchback
= (char *)dup
+ oldlen
- (char *)hdr
== offset
+ len
;
840 ASSERT(*needscanp
== 0);
843 * If we matched it exactly we just need to get rid of it from
844 * the bestfree table.
846 if (matchfront
&& matchback
) {
848 needscan
= (hdr
->bestfree
[2].offset
!= 0);
850 xfs_dir2_data_freeremove(hdr
, dfp
, needlogp
);
854 * We match the first part of the entry.
855 * Make a new entry with the remaining freespace.
857 else if (matchfront
) {
858 newdup
= (xfs_dir2_data_unused_t
*)((char *)hdr
+ offset
+ len
);
859 newdup
->freetag
= cpu_to_be16(XFS_DIR2_DATA_FREE_TAG
);
860 newdup
->length
= cpu_to_be16(oldlen
- len
);
861 *xfs_dir2_data_unused_tag_p(newdup
) =
862 cpu_to_be16((char *)newdup
- (char *)hdr
);
863 xfs_dir2_data_log_unused(tp
, bp
, newdup
);
865 * If it was in the table, remove it and add the new one.
868 xfs_dir2_data_freeremove(hdr
, dfp
, needlogp
);
869 dfp
= xfs_dir2_data_freeinsert(hdr
, newdup
, needlogp
);
871 ASSERT(dfp
->length
== newdup
->length
);
872 ASSERT(be16_to_cpu(dfp
->offset
) == (char *)newdup
- (char *)hdr
);
874 * If we got inserted at the last slot,
875 * that means we don't know if there was a better
876 * choice for the last slot, or not. Rescan.
878 needscan
= dfp
== &hdr
->bestfree
[2];
882 * We match the last part of the entry.
883 * Trim the allocated space off the tail of the entry.
885 else if (matchback
) {
887 newdup
->length
= cpu_to_be16(((char *)hdr
+ offset
) - (char *)newdup
);
888 *xfs_dir2_data_unused_tag_p(newdup
) =
889 cpu_to_be16((char *)newdup
- (char *)hdr
);
890 xfs_dir2_data_log_unused(tp
, bp
, newdup
);
892 * If it was in the table, remove it and add the new one.
895 xfs_dir2_data_freeremove(hdr
, dfp
, needlogp
);
896 dfp
= xfs_dir2_data_freeinsert(hdr
, newdup
, needlogp
);
898 ASSERT(dfp
->length
== newdup
->length
);
899 ASSERT(be16_to_cpu(dfp
->offset
) == (char *)newdup
- (char *)hdr
);
901 * If we got inserted at the last slot,
902 * that means we don't know if there was a better
903 * choice for the last slot, or not. Rescan.
905 needscan
= dfp
== &hdr
->bestfree
[2];
909 * Poking out the middle of an entry.
910 * Make two new entries.
914 newdup
->length
= cpu_to_be16(((char *)hdr
+ offset
) - (char *)newdup
);
915 *xfs_dir2_data_unused_tag_p(newdup
) =
916 cpu_to_be16((char *)newdup
- (char *)hdr
);
917 xfs_dir2_data_log_unused(tp
, bp
, newdup
);
918 newdup2
= (xfs_dir2_data_unused_t
*)((char *)hdr
+ offset
+ len
);
919 newdup2
->freetag
= cpu_to_be16(XFS_DIR2_DATA_FREE_TAG
);
920 newdup2
->length
= cpu_to_be16(oldlen
- len
- be16_to_cpu(newdup
->length
));
921 *xfs_dir2_data_unused_tag_p(newdup2
) =
922 cpu_to_be16((char *)newdup2
- (char *)hdr
);
923 xfs_dir2_data_log_unused(tp
, bp
, newdup2
);
925 * If the old entry was in the table, we need to scan
926 * if the 3rd entry was valid, since these entries
927 * are smaller than the old one.
928 * If we don't need to scan that means there were 1 or 2
929 * entries in the table, and removing the old and adding
930 * the 2 new will work.
933 needscan
= (hdr
->bestfree
[2].length
!= 0);
935 xfs_dir2_data_freeremove(hdr
, dfp
, needlogp
);
936 xfs_dir2_data_freeinsert(hdr
, newdup
, needlogp
);
937 xfs_dir2_data_freeinsert(hdr
, newdup2
,
942 *needscanp
= needscan
;