2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
3 * Copyright (c) 2013 Red Hat, Inc.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it would be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 #include "xfs_format.h"
22 #include "xfs_log_format.h"
23 #include "xfs_trans_resv.h"
26 #include "xfs_mount.h"
27 #include "xfs_da_format.h"
28 #include "xfs_da_btree.h"
29 #include "xfs_inode.h"
31 #include "xfs_dir2_priv.h"
32 #include "xfs_error.h"
33 #include "xfs_trans.h"
34 #include "xfs_buf_item.h"
35 #include "xfs_cksum.h"
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_dir3_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;
68 bf = xfs_dir3_data_bestfree_p(hdr);
69 p = (char *)xfs_dir3_data_entry_p(hdr);
72 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC):
73 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC):
74 btp = xfs_dir2_block_tail_p(mp, hdr);
75 lep = xfs_dir2_block_leaf_p(btp);
78 case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
79 case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
80 endp = (char *)hdr + mp->m_dirblksize;
83 XFS_ERROR_REPORT("Bad Magic", XFS_ERRLEVEL_LOW, mp);
87 count = lastfree = freeseen = 0;
89 * Account for zero bestfree entries.
92 XFS_WANT_CORRUPTED_RETURN(!bf[0].offset);
96 XFS_WANT_CORRUPTED_RETURN(!bf[1].offset);
100 XFS_WANT_CORRUPTED_RETURN(!bf[2].offset);
104 XFS_WANT_CORRUPTED_RETURN(be16_to_cpu(bf[0].length) >=
105 be16_to_cpu(bf[1].length));
106 XFS_WANT_CORRUPTED_RETURN(be16_to_cpu(bf[1].length) >=
107 be16_to_cpu(bf[2].length));
109 * Loop over the data/unused entries.
112 dup = (xfs_dir2_data_unused_t *)p;
114 * If it's unused, look for the space in the bestfree table.
115 * If we find it, account for that, else make sure it
116 * doesn't need to be there.
118 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
119 XFS_WANT_CORRUPTED_RETURN(lastfree == 0);
120 XFS_WANT_CORRUPTED_RETURN(
121 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)) ==
122 (char *)dup - (char *)hdr);
123 dfp = xfs_dir2_data_freefind(hdr, dup);
126 XFS_WANT_CORRUPTED_RETURN(
127 (freeseen & (1 << i)) == 0);
130 XFS_WANT_CORRUPTED_RETURN(
131 be16_to_cpu(dup->length) <=
132 be16_to_cpu(bf[2].length));
134 p += be16_to_cpu(dup->length);
139 * It's a real entry. Validate the fields.
140 * If this is a block directory then make sure it's
141 * in the leaf section of the block.
142 * The linear search is crude but this is DEBUG code.
144 dep = (xfs_dir2_data_entry_t *)p;
145 XFS_WANT_CORRUPTED_RETURN(dep->namelen != 0);
146 XFS_WANT_CORRUPTED_RETURN(
147 !xfs_dir_ino_validate(mp, be64_to_cpu(dep->inumber)));
148 XFS_WANT_CORRUPTED_RETURN(
149 be16_to_cpu(*xfs_dir3_data_entry_tag_p(mp, dep)) ==
150 (char *)dep - (char *)hdr);
151 XFS_WANT_CORRUPTED_RETURN(
152 xfs_dir3_dirent_get_ftype(mp, dep) < XFS_DIR3_FT_MAX);
155 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
156 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) {
157 addr = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
158 (xfs_dir2_data_aoff_t)
159 ((char *)dep - (char *)hdr));
160 name.name = dep->name;
161 name.len = dep->namelen;
162 hash = mp->m_dirnameops->hashname(&name);
163 for (i = 0; i < be32_to_cpu(btp->count); i++) {
164 if (be32_to_cpu(lep[i].address) == addr &&
165 be32_to_cpu(lep[i].hashval) == hash)
168 XFS_WANT_CORRUPTED_RETURN(i < be32_to_cpu(btp->count));
170 p += xfs_dir3_data_entsize(mp, dep->namelen);
173 * Need to have seen all the entries and all the bestfree slots.
175 XFS_WANT_CORRUPTED_RETURN(freeseen == 7);
176 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
177 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) {
178 for (i = stale = 0; i < be32_to_cpu(btp->count); i++) {
179 if (lep[i].address ==
180 cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
183 XFS_WANT_CORRUPTED_RETURN(
184 be32_to_cpu(lep[i].hashval) >=
185 be32_to_cpu(lep[i - 1].hashval));
187 XFS_WANT_CORRUPTED_RETURN(count ==
188 be32_to_cpu(btp->count) - be32_to_cpu(btp->stale));
189 XFS_WANT_CORRUPTED_RETURN(stale == be32_to_cpu(btp->stale));
195 xfs_dir3_data_verify(
198 struct xfs_mount *mp = bp->b_target->bt_mount;
199 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
201 if (xfs_sb_version_hascrc(&mp->m_sb)) {
202 if (hdr3->magic != cpu_to_be32(XFS_DIR3_DATA_MAGIC))
204 if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_uuid))
206 if (be64_to_cpu(hdr3->blkno) != bp->b_bn)
209 if (hdr3->magic != cpu_to_be32(XFS_DIR2_DATA_MAGIC))
212 if (__xfs_dir3_data_check(NULL, bp))
218 * Readahead of the first block of the directory when it is opened is completely
219 * oblivious to the format of the directory. Hence we can either get a block
220 * format buffer or a data format buffer on readahead.
223 xfs_dir3_data_reada_verify(
226 struct xfs_mount *mp = bp->b_target->bt_mount;
227 struct xfs_dir2_data_hdr *hdr = bp->b_addr;
229 switch (hdr->magic) {
230 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC):
231 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC):
232 bp->b_ops = &xfs_dir3_block_buf_ops;
233 bp->b_ops->verify_read(bp);
235 case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
236 case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
237 xfs_dir3_data_verify(bp);
240 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, hdr);
241 xfs_buf_ioerror(bp, EFSCORRUPTED);
247 xfs_dir3_data_read_verify(
250 struct xfs_mount *mp = bp->b_target->bt_mount;
252 if ((xfs_sb_version_hascrc(&mp->m_sb) &&
253 !xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
254 XFS_DIR3_DATA_CRC_OFF)) ||
255 !xfs_dir3_data_verify(bp)) {
256 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
257 xfs_buf_ioerror(bp, EFSCORRUPTED);
262 xfs_dir3_data_write_verify(
265 struct xfs_mount *mp = bp->b_target->bt_mount;
266 struct xfs_buf_log_item *bip = bp->b_fspriv;
267 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
269 if (!xfs_dir3_data_verify(bp)) {
270 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
271 xfs_buf_ioerror(bp, EFSCORRUPTED);
275 if (!xfs_sb_version_hascrc(&mp->m_sb))
279 hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn);
281 xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DIR3_DATA_CRC_OFF);
284 const struct xfs_buf_ops xfs_dir3_data_buf_ops = {
285 .verify_read = xfs_dir3_data_read_verify,
286 .verify_write = xfs_dir3_data_write_verify,
289 static const struct xfs_buf_ops xfs_dir3_data_reada_buf_ops = {
290 .verify_read = xfs_dir3_data_reada_verify,
291 .verify_write = xfs_dir3_data_write_verify,
297 struct xfs_trans *tp,
298 struct xfs_inode *dp,
300 xfs_daddr_t mapped_bno,
301 struct xfs_buf **bpp)
305 err = xfs_da_read_buf(tp, dp, bno, mapped_bno, bpp,
306 XFS_DATA_FORK, &xfs_dir3_data_buf_ops);
308 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_DATA_BUF);
313 xfs_dir3_data_readahead(
314 struct xfs_trans *tp,
315 struct xfs_inode *dp,
317 xfs_daddr_t mapped_bno)
319 return xfs_da_reada_buf(tp, dp, bno, mapped_bno,
320 XFS_DATA_FORK, &xfs_dir3_data_reada_buf_ops);
324 * Given a data block and an unused entry from that block,
325 * return the bestfree entry if any that corresponds to it.
327 xfs_dir2_data_free_t *
328 xfs_dir2_data_freefind(
329 xfs_dir2_data_hdr_t *hdr, /* data block */
330 xfs_dir2_data_unused_t *dup) /* data unused entry */
332 xfs_dir2_data_free_t *dfp; /* bestfree entry */
333 xfs_dir2_data_aoff_t off; /* offset value needed */
334 struct xfs_dir2_data_free *bf;
336 int matched; /* matched the value */
337 int seenzero; /* saw a 0 bestfree entry */
340 off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr);
341 bf = xfs_dir3_data_bestfree_p(hdr);
345 * Validate some consistency in the bestfree table.
346 * Check order, non-overlapping entries, and if we find the
347 * one we're looking for it has to be exact.
349 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
350 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
351 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
352 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
353 for (dfp = &bf[0], seenzero = matched = 0;
354 dfp < &bf[XFS_DIR2_DATA_FD_COUNT];
357 ASSERT(!dfp->length);
361 ASSERT(seenzero == 0);
362 if (be16_to_cpu(dfp->offset) == off) {
364 ASSERT(dfp->length == dup->length);
365 } else if (off < be16_to_cpu(dfp->offset))
366 ASSERT(off + be16_to_cpu(dup->length) <= be16_to_cpu(dfp->offset));
368 ASSERT(be16_to_cpu(dfp->offset) + be16_to_cpu(dfp->length) <= off);
369 ASSERT(matched || be16_to_cpu(dfp->length) >= be16_to_cpu(dup->length));
371 ASSERT(be16_to_cpu(dfp[-1].length) >= be16_to_cpu(dfp[0].length));
375 * If this is smaller than the smallest bestfree entry,
376 * it can't be there since they're sorted.
378 if (be16_to_cpu(dup->length) <
379 be16_to_cpu(bf[XFS_DIR2_DATA_FD_COUNT - 1].length))
382 * Look at the three bestfree entries for our guy.
384 for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) {
387 if (be16_to_cpu(dfp->offset) == off)
391 * Didn't find it. This only happens if there are duplicate lengths.
397 * Insert an unused-space entry into the bestfree table.
399 xfs_dir2_data_free_t * /* entry inserted */
400 xfs_dir2_data_freeinsert(
401 xfs_dir2_data_hdr_t *hdr, /* data block pointer */
402 xfs_dir2_data_unused_t *dup, /* unused space */
403 int *loghead) /* log the data header (out) */
405 xfs_dir2_data_free_t *dfp; /* bestfree table pointer */
406 xfs_dir2_data_free_t new; /* new bestfree entry */
408 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
409 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
410 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
411 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
413 dfp = xfs_dir3_data_bestfree_p(hdr);
414 new.length = dup->length;
415 new.offset = cpu_to_be16((char *)dup - (char *)hdr);
418 * Insert at position 0, 1, or 2; or not at all.
420 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[0].length)) {
427 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[1].length)) {
433 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[2].length)) {
442 * Remove a bestfree entry from the table.
445 xfs_dir2_data_freeremove(
446 xfs_dir2_data_hdr_t *hdr, /* data block header */
447 xfs_dir2_data_free_t *dfp, /* bestfree entry pointer */
448 int *loghead) /* out: log data header */
450 struct xfs_dir2_data_free *bf;
452 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
453 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
454 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
455 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
458 * It's the first entry, slide the next 2 up.
460 bf = xfs_dir3_data_bestfree_p(hdr);
466 * It's the second entry, slide the 3rd entry up.
468 else if (dfp == &bf[1])
471 * Must be the last entry.
474 ASSERT(dfp == &bf[2]);
476 * Clear the 3rd entry, must be zero now.
484 * Given a data block, reconstruct its bestfree map.
487 xfs_dir2_data_freescan(
488 xfs_mount_t *mp, /* filesystem mount point */
489 xfs_dir2_data_hdr_t *hdr, /* data block header */
490 int *loghead) /* out: log data header */
492 xfs_dir2_block_tail_t *btp; /* block tail */
493 xfs_dir2_data_entry_t *dep; /* active data entry */
494 xfs_dir2_data_unused_t *dup; /* unused data entry */
495 struct xfs_dir2_data_free *bf;
496 char *endp; /* end of block's data */
497 char *p; /* current entry pointer */
499 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
500 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
501 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
502 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
505 * Start by clearing the table.
507 bf = xfs_dir3_data_bestfree_p(hdr);
508 memset(bf, 0, sizeof(*bf) * XFS_DIR2_DATA_FD_COUNT);
513 p = (char *)xfs_dir3_data_entry_p(hdr);
514 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
515 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) {
516 btp = xfs_dir2_block_tail_p(mp, hdr);
517 endp = (char *)xfs_dir2_block_leaf_p(btp);
519 endp = (char *)hdr + mp->m_dirblksize;
521 * Loop over the block's entries.
524 dup = (xfs_dir2_data_unused_t *)p;
526 * If it's a free entry, insert it.
528 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
529 ASSERT((char *)dup - (char *)hdr ==
530 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)));
531 xfs_dir2_data_freeinsert(hdr, dup, loghead);
532 p += be16_to_cpu(dup->length);
535 * For active entries, check their tags and skip them.
538 dep = (xfs_dir2_data_entry_t *)p;
539 ASSERT((char *)dep - (char *)hdr ==
540 be16_to_cpu(*xfs_dir3_data_entry_tag_p(mp, dep)));
541 p += xfs_dir3_data_entsize(mp, dep->namelen);
547 * Initialize a data block at the given block number in the directory.
548 * Give back the buffer for the created block.
552 xfs_da_args_t *args, /* directory operation args */
553 xfs_dir2_db_t blkno, /* logical dir block number */
554 struct xfs_buf **bpp) /* output block buffer */
556 struct xfs_buf *bp; /* block buffer */
557 xfs_dir2_data_hdr_t *hdr; /* data block header */
558 xfs_inode_t *dp; /* incore directory inode */
559 xfs_dir2_data_unused_t *dup; /* unused entry pointer */
560 struct xfs_dir2_data_free *bf;
561 int error; /* error return value */
562 int i; /* bestfree index */
563 xfs_mount_t *mp; /* filesystem mount point */
564 xfs_trans_t *tp; /* transaction pointer */
571 * Get the buffer set up for the block.
573 error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, blkno), -1, &bp,
577 bp->b_ops = &xfs_dir3_data_buf_ops;
578 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_DATA_BUF);
581 * Initialize the header.
584 if (xfs_sb_version_hascrc(&mp->m_sb)) {
585 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
587 memset(hdr3, 0, sizeof(*hdr3));
588 hdr3->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
589 hdr3->blkno = cpu_to_be64(bp->b_bn);
590 hdr3->owner = cpu_to_be64(dp->i_ino);
591 uuid_copy(&hdr3->uuid, &mp->m_sb.sb_uuid);
594 hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
596 bf = xfs_dir3_data_bestfree_p(hdr);
597 bf[0].offset = cpu_to_be16(xfs_dir3_data_entry_offset(hdr));
598 for (i = 1; i < XFS_DIR2_DATA_FD_COUNT; i++) {
604 * Set up an unused entry for the block's body.
606 dup = xfs_dir3_data_unused_p(hdr);
607 dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
609 t = mp->m_dirblksize - (uint)xfs_dir3_data_entry_offset(hdr);
610 bf[0].length = cpu_to_be16(t);
611 dup->length = cpu_to_be16(t);
612 *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16((char *)dup - (char *)hdr);
614 * Log it and return it.
616 xfs_dir2_data_log_header(tp, bp);
617 xfs_dir2_data_log_unused(tp, bp, dup);
623 * Log an active data entry from the block.
626 xfs_dir2_data_log_entry(
627 struct xfs_trans *tp,
629 xfs_dir2_data_entry_t *dep) /* data entry pointer */
631 struct xfs_dir2_data_hdr *hdr = bp->b_addr;
632 struct xfs_mount *mp = tp->t_mountp;
634 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
635 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
636 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
637 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
639 xfs_trans_log_buf(tp, bp, (uint)((char *)dep - (char *)hdr),
640 (uint)((char *)(xfs_dir3_data_entry_tag_p(mp, dep) + 1) -
645 * Log a data block header.
648 xfs_dir2_data_log_header(
649 struct xfs_trans *tp,
652 xfs_dir2_data_hdr_t *hdr = bp->b_addr;
654 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
655 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
656 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
657 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
659 xfs_trans_log_buf(tp, bp, 0, xfs_dir3_data_entry_offset(hdr) - 1);
663 * Log a data unused entry.
666 xfs_dir2_data_log_unused(
667 struct xfs_trans *tp,
669 xfs_dir2_data_unused_t *dup) /* data unused pointer */
671 xfs_dir2_data_hdr_t *hdr = bp->b_addr;
673 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
674 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
675 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
676 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
679 * Log the first part of the unused entry.
681 xfs_trans_log_buf(tp, bp, (uint)((char *)dup - (char *)hdr),
682 (uint)((char *)&dup->length + sizeof(dup->length) -
685 * Log the end (tag) of the unused entry.
687 xfs_trans_log_buf(tp, bp,
688 (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr),
689 (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr +
690 sizeof(xfs_dir2_data_off_t) - 1));
694 * Make a byte range in the data block unused.
695 * Its current contents are unimportant.
698 xfs_dir2_data_make_free(
699 struct xfs_trans *tp,
701 xfs_dir2_data_aoff_t offset, /* starting byte offset */
702 xfs_dir2_data_aoff_t len, /* length in bytes */
703 int *needlogp, /* out: log header */
704 int *needscanp) /* out: regen bestfree */
706 xfs_dir2_data_hdr_t *hdr; /* data block pointer */
707 xfs_dir2_data_free_t *dfp; /* bestfree pointer */
708 char *endptr; /* end of data area */
709 xfs_mount_t *mp; /* filesystem mount point */
710 int needscan; /* need to regen bestfree */
711 xfs_dir2_data_unused_t *newdup; /* new unused entry */
712 xfs_dir2_data_unused_t *postdup; /* unused entry after us */
713 xfs_dir2_data_unused_t *prevdup; /* unused entry before us */
714 struct xfs_dir2_data_free *bf;
720 * Figure out where the end of the data area is.
722 if (hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
723 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC))
724 endptr = (char *)hdr + mp->m_dirblksize;
726 xfs_dir2_block_tail_t *btp; /* block tail */
728 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
729 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
730 btp = xfs_dir2_block_tail_p(mp, hdr);
731 endptr = (char *)xfs_dir2_block_leaf_p(btp);
734 * If this isn't the start of the block, then back up to
735 * the previous entry and see if it's free.
737 if (offset > xfs_dir3_data_entry_offset(hdr)) {
738 __be16 *tagp; /* tag just before us */
740 tagp = (__be16 *)((char *)hdr + offset) - 1;
741 prevdup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
742 if (be16_to_cpu(prevdup->freetag) != XFS_DIR2_DATA_FREE_TAG)
747 * If this isn't the end of the block, see if the entry after
750 if ((char *)hdr + offset + len < endptr) {
752 (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
753 if (be16_to_cpu(postdup->freetag) != XFS_DIR2_DATA_FREE_TAG)
757 ASSERT(*needscanp == 0);
760 * Previous and following entries are both free,
761 * merge everything into a single free entry.
763 bf = xfs_dir3_data_bestfree_p(hdr);
764 if (prevdup && postdup) {
765 xfs_dir2_data_free_t *dfp2; /* another bestfree pointer */
768 * See if prevdup and/or postdup are in bestfree table.
770 dfp = xfs_dir2_data_freefind(hdr, prevdup);
771 dfp2 = xfs_dir2_data_freefind(hdr, postdup);
773 * We need a rescan unless there are exactly 2 free entries
774 * namely our two. Then we know what's happening, otherwise
775 * since the third bestfree is there, there might be more
778 needscan = (bf[2].length != 0);
780 * Fix up the new big freespace.
782 be16_add_cpu(&prevdup->length, len + be16_to_cpu(postdup->length));
783 *xfs_dir2_data_unused_tag_p(prevdup) =
784 cpu_to_be16((char *)prevdup - (char *)hdr);
785 xfs_dir2_data_log_unused(tp, bp, prevdup);
788 * Has to be the case that entries 0 and 1 are
789 * dfp and dfp2 (don't know which is which), and
791 * Remove entry 1 first then entry 0.
799 xfs_dir2_data_freeremove(hdr, dfp2, needlogp);
800 xfs_dir2_data_freeremove(hdr, dfp, needlogp);
802 * Now insert the new entry.
804 dfp = xfs_dir2_data_freeinsert(hdr, prevdup, needlogp);
805 ASSERT(dfp == &bf[0]);
806 ASSERT(dfp->length == prevdup->length);
807 ASSERT(!dfp[1].length);
808 ASSERT(!dfp[2].length);
812 * The entry before us is free, merge with it.
815 dfp = xfs_dir2_data_freefind(hdr, prevdup);
816 be16_add_cpu(&prevdup->length, len);
817 *xfs_dir2_data_unused_tag_p(prevdup) =
818 cpu_to_be16((char *)prevdup - (char *)hdr);
819 xfs_dir2_data_log_unused(tp, bp, prevdup);
821 * If the previous entry was in the table, the new entry
822 * is longer, so it will be in the table too. Remove
823 * the old one and add the new one.
826 xfs_dir2_data_freeremove(hdr, dfp, needlogp);
827 xfs_dir2_data_freeinsert(hdr, prevdup, needlogp);
830 * Otherwise we need a scan if the new entry is big enough.
833 needscan = be16_to_cpu(prevdup->length) >
834 be16_to_cpu(bf[2].length);
838 * The following entry is free, merge with it.
841 dfp = xfs_dir2_data_freefind(hdr, postdup);
842 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
843 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
844 newdup->length = cpu_to_be16(len + be16_to_cpu(postdup->length));
845 *xfs_dir2_data_unused_tag_p(newdup) =
846 cpu_to_be16((char *)newdup - (char *)hdr);
847 xfs_dir2_data_log_unused(tp, bp, newdup);
849 * If the following entry was in the table, the new entry
850 * is longer, so it will be in the table too. Remove
851 * the old one and add the new one.
854 xfs_dir2_data_freeremove(hdr, dfp, needlogp);
855 xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
858 * Otherwise we need a scan if the new entry is big enough.
861 needscan = be16_to_cpu(newdup->length) >
862 be16_to_cpu(bf[2].length);
866 * Neither neighbor is free. Make a new entry.
869 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
870 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
871 newdup->length = cpu_to_be16(len);
872 *xfs_dir2_data_unused_tag_p(newdup) =
873 cpu_to_be16((char *)newdup - (char *)hdr);
874 xfs_dir2_data_log_unused(tp, bp, newdup);
875 xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
877 *needscanp = needscan;
881 * Take a byte range out of an existing unused space and make it un-free.
884 xfs_dir2_data_use_free(
885 struct xfs_trans *tp,
887 xfs_dir2_data_unused_t *dup, /* unused entry */
888 xfs_dir2_data_aoff_t offset, /* starting offset to use */
889 xfs_dir2_data_aoff_t len, /* length to use */
890 int *needlogp, /* out: need to log header */
891 int *needscanp) /* out: need regen bestfree */
893 xfs_dir2_data_hdr_t *hdr; /* data block header */
894 xfs_dir2_data_free_t *dfp; /* bestfree pointer */
895 int matchback; /* matches end of freespace */
896 int matchfront; /* matches start of freespace */
897 int needscan; /* need to regen bestfree */
898 xfs_dir2_data_unused_t *newdup; /* new unused entry */
899 xfs_dir2_data_unused_t *newdup2; /* another new unused entry */
900 int oldlen; /* old unused entry's length */
901 struct xfs_dir2_data_free *bf;
904 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
905 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
906 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
907 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
908 ASSERT(be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG);
909 ASSERT(offset >= (char *)dup - (char *)hdr);
910 ASSERT(offset + len <= (char *)dup + be16_to_cpu(dup->length) - (char *)hdr);
911 ASSERT((char *)dup - (char *)hdr == be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)));
913 * Look up the entry in the bestfree table.
915 dfp = xfs_dir2_data_freefind(hdr, dup);
916 oldlen = be16_to_cpu(dup->length);
917 bf = xfs_dir3_data_bestfree_p(hdr);
918 ASSERT(dfp || oldlen <= be16_to_cpu(bf[2].length));
920 * Check for alignment with front and back of the entry.
922 matchfront = (char *)dup - (char *)hdr == offset;
923 matchback = (char *)dup + oldlen - (char *)hdr == offset + len;
924 ASSERT(*needscanp == 0);
927 * If we matched it exactly we just need to get rid of it from
928 * the bestfree table.
930 if (matchfront && matchback) {
932 needscan = (bf[2].offset != 0);
934 xfs_dir2_data_freeremove(hdr, dfp, needlogp);
938 * We match the first part of the entry.
939 * Make a new entry with the remaining freespace.
941 else if (matchfront) {
942 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
943 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
944 newdup->length = cpu_to_be16(oldlen - len);
945 *xfs_dir2_data_unused_tag_p(newdup) =
946 cpu_to_be16((char *)newdup - (char *)hdr);
947 xfs_dir2_data_log_unused(tp, bp, newdup);
949 * If it was in the table, remove it and add the new one.
952 xfs_dir2_data_freeremove(hdr, dfp, needlogp);
953 dfp = xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
955 ASSERT(dfp->length == newdup->length);
956 ASSERT(be16_to_cpu(dfp->offset) == (char *)newdup - (char *)hdr);
958 * If we got inserted at the last slot,
959 * that means we don't know if there was a better
960 * choice for the last slot, or not. Rescan.
962 needscan = dfp == &bf[2];
966 * We match the last part of the entry.
967 * Trim the allocated space off the tail of the entry.
969 else if (matchback) {
971 newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup);
972 *xfs_dir2_data_unused_tag_p(newdup) =
973 cpu_to_be16((char *)newdup - (char *)hdr);
974 xfs_dir2_data_log_unused(tp, bp, newdup);
976 * If it was in the table, remove it and add the new one.
979 xfs_dir2_data_freeremove(hdr, dfp, needlogp);
980 dfp = xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
982 ASSERT(dfp->length == newdup->length);
983 ASSERT(be16_to_cpu(dfp->offset) == (char *)newdup - (char *)hdr);
985 * If we got inserted at the last slot,
986 * that means we don't know if there was a better
987 * choice for the last slot, or not. Rescan.
989 needscan = dfp == &bf[2];
993 * Poking out the middle of an entry.
994 * Make two new entries.
998 newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup);
999 *xfs_dir2_data_unused_tag_p(newdup) =
1000 cpu_to_be16((char *)newdup - (char *)hdr);
1001 xfs_dir2_data_log_unused(tp, bp, newdup);
1002 newdup2 = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
1003 newdup2->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
1004 newdup2->length = cpu_to_be16(oldlen - len - be16_to_cpu(newdup->length));
1005 *xfs_dir2_data_unused_tag_p(newdup2) =
1006 cpu_to_be16((char *)newdup2 - (char *)hdr);
1007 xfs_dir2_data_log_unused(tp, bp, newdup2);
1009 * If the old entry was in the table, we need to scan
1010 * if the 3rd entry was valid, since these entries
1011 * are smaller than the old one.
1012 * If we don't need to scan that means there were 1 or 2
1013 * entries in the table, and removing the old and adding
1014 * the 2 new will work.
1017 needscan = (bf[2].length != 0);
1019 xfs_dir2_data_freeremove(hdr, dfp, needlogp);
1020 xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
1021 xfs_dir2_data_freeinsert(hdr, newdup2,
1026 *needscanp = needscan;