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5792664070
Replace the current mess of dir2 headers with just three that have a clear purpose: - xfs_dir2_format.h for all format definitions, including the inline helpers to access our variable size structures - xfs_dir2_priv.h for all prototypes that are internal to the dir2 code and not needed by anything outside of the directory code. For this purpose xfs_da_btree.c, and phase6.c in xfs_repair are considered part of the directory code. - xfs_dir2.h for the public interface to the directory code In addition to the reshuffle I have also update the comments to not only match the new file structure, but also to describe the directory format better. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
839 lines
25 KiB
C
839 lines
25 KiB
C
/*
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* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
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* All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it would be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "xfs.h"
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#include "xfs_fs.h"
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#include "xfs_types.h"
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#include "xfs_log.h"
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#include "xfs_inum.h"
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#include "xfs_trans.h"
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#include "xfs_sb.h"
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#include "xfs_ag.h"
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#include "xfs_mount.h"
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#include "xfs_da_btree.h"
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#include "xfs_bmap_btree.h"
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#include "xfs_dinode.h"
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#include "xfs_inode.h"
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#include "xfs_dir2_format.h"
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#include "xfs_dir2_priv.h"
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#include "xfs_error.h"
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STATIC xfs_dir2_data_free_t *
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xfs_dir2_data_freefind(xfs_dir2_data_hdr_t *hdr, xfs_dir2_data_unused_t *dup);
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#ifdef DEBUG
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/*
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* Check the consistency of the data block.
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* The input can also be a block-format directory.
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* Pop an assert if we find anything bad.
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*/
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void
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xfs_dir2_data_check(
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xfs_inode_t *dp, /* incore inode pointer */
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xfs_dabuf_t *bp) /* data block's buffer */
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{
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xfs_dir2_dataptr_t addr; /* addr for leaf lookup */
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xfs_dir2_data_free_t *bf; /* bestfree table */
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xfs_dir2_block_tail_t *btp=NULL; /* block tail */
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int count; /* count of entries found */
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xfs_dir2_data_hdr_t *hdr; /* data block header */
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xfs_dir2_data_entry_t *dep; /* data entry */
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xfs_dir2_data_free_t *dfp; /* bestfree entry */
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xfs_dir2_data_unused_t *dup; /* unused entry */
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char *endp; /* end of useful data */
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int freeseen; /* mask of bestfrees seen */
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xfs_dahash_t hash; /* hash of current name */
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int i; /* leaf index */
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int lastfree; /* last entry was unused */
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xfs_dir2_leaf_entry_t *lep=NULL; /* block leaf entries */
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xfs_mount_t *mp; /* filesystem mount point */
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char *p; /* current data position */
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int stale; /* count of stale leaves */
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struct xfs_name name;
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mp = dp->i_mount;
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hdr = bp->data;
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bf = hdr->bestfree;
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p = (char *)(hdr + 1);
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if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)) {
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btp = xfs_dir2_block_tail_p(mp, hdr);
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lep = xfs_dir2_block_leaf_p(btp);
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endp = (char *)lep;
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} else {
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ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC));
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endp = (char *)hdr + mp->m_dirblksize;
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}
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count = lastfree = freeseen = 0;
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/*
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* Account for zero bestfree entries.
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*/
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if (!bf[0].length) {
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ASSERT(!bf[0].offset);
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freeseen |= 1 << 0;
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}
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if (!bf[1].length) {
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ASSERT(!bf[1].offset);
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freeseen |= 1 << 1;
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}
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if (!bf[2].length) {
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ASSERT(!bf[2].offset);
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freeseen |= 1 << 2;
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}
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ASSERT(be16_to_cpu(bf[0].length) >= be16_to_cpu(bf[1].length));
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ASSERT(be16_to_cpu(bf[1].length) >= be16_to_cpu(bf[2].length));
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/*
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* Loop over the data/unused entries.
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*/
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while (p < endp) {
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dup = (xfs_dir2_data_unused_t *)p;
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/*
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* If it's unused, look for the space in the bestfree table.
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* If we find it, account for that, else make sure it
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* doesn't need to be there.
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*/
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if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
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ASSERT(lastfree == 0);
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ASSERT(be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)) ==
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(char *)dup - (char *)hdr);
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dfp = xfs_dir2_data_freefind(hdr, dup);
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if (dfp) {
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i = (int)(dfp - bf);
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ASSERT((freeseen & (1 << i)) == 0);
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freeseen |= 1 << i;
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} else {
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ASSERT(be16_to_cpu(dup->length) <=
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be16_to_cpu(bf[2].length));
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}
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p += be16_to_cpu(dup->length);
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lastfree = 1;
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continue;
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}
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/*
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* It's a real entry. Validate the fields.
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* If this is a block directory then make sure it's
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* in the leaf section of the block.
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* The linear search is crude but this is DEBUG code.
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*/
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dep = (xfs_dir2_data_entry_t *)p;
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ASSERT(dep->namelen != 0);
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ASSERT(xfs_dir_ino_validate(mp, be64_to_cpu(dep->inumber)) == 0);
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ASSERT(be16_to_cpu(*xfs_dir2_data_entry_tag_p(dep)) ==
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(char *)dep - (char *)hdr);
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count++;
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lastfree = 0;
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if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)) {
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addr = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
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(xfs_dir2_data_aoff_t)
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((char *)dep - (char *)hdr));
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name.name = dep->name;
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name.len = dep->namelen;
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hash = mp->m_dirnameops->hashname(&name);
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for (i = 0; i < be32_to_cpu(btp->count); i++) {
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if (be32_to_cpu(lep[i].address) == addr &&
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be32_to_cpu(lep[i].hashval) == hash)
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break;
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}
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ASSERT(i < be32_to_cpu(btp->count));
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}
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p += xfs_dir2_data_entsize(dep->namelen);
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}
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/*
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* Need to have seen all the entries and all the bestfree slots.
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*/
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ASSERT(freeseen == 7);
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if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)) {
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for (i = stale = 0; i < be32_to_cpu(btp->count); i++) {
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if (lep[i].address ==
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cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
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stale++;
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if (i > 0)
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ASSERT(be32_to_cpu(lep[i].hashval) >= be32_to_cpu(lep[i - 1].hashval));
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}
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ASSERT(count == be32_to_cpu(btp->count) - be32_to_cpu(btp->stale));
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ASSERT(stale == be32_to_cpu(btp->stale));
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}
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}
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#endif
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/*
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* Given a data block and an unused entry from that block,
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* return the bestfree entry if any that corresponds to it.
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*/
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STATIC xfs_dir2_data_free_t *
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xfs_dir2_data_freefind(
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xfs_dir2_data_hdr_t *hdr, /* data block */
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xfs_dir2_data_unused_t *dup) /* data unused entry */
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{
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xfs_dir2_data_free_t *dfp; /* bestfree entry */
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xfs_dir2_data_aoff_t off; /* offset value needed */
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#if defined(DEBUG) && defined(__KERNEL__)
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int matched; /* matched the value */
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int seenzero; /* saw a 0 bestfree entry */
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#endif
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off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr);
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#if defined(DEBUG) && defined(__KERNEL__)
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/*
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* Validate some consistency in the bestfree table.
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* Check order, non-overlapping entries, and if we find the
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* one we're looking for it has to be exact.
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*/
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ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
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hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC));
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for (dfp = &hdr->bestfree[0], seenzero = matched = 0;
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dfp < &hdr->bestfree[XFS_DIR2_DATA_FD_COUNT];
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dfp++) {
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if (!dfp->offset) {
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ASSERT(!dfp->length);
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seenzero = 1;
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continue;
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}
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ASSERT(seenzero == 0);
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if (be16_to_cpu(dfp->offset) == off) {
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matched = 1;
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ASSERT(dfp->length == dup->length);
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} else if (off < be16_to_cpu(dfp->offset))
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ASSERT(off + be16_to_cpu(dup->length) <= be16_to_cpu(dfp->offset));
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else
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ASSERT(be16_to_cpu(dfp->offset) + be16_to_cpu(dfp->length) <= off);
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ASSERT(matched || be16_to_cpu(dfp->length) >= be16_to_cpu(dup->length));
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if (dfp > &hdr->bestfree[0])
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ASSERT(be16_to_cpu(dfp[-1].length) >= be16_to_cpu(dfp[0].length));
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}
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#endif
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/*
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* If this is smaller than the smallest bestfree entry,
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* it can't be there since they're sorted.
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*/
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if (be16_to_cpu(dup->length) <
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be16_to_cpu(hdr->bestfree[XFS_DIR2_DATA_FD_COUNT - 1].length))
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return NULL;
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/*
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* Look at the three bestfree entries for our guy.
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*/
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for (dfp = &hdr->bestfree[0];
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dfp < &hdr->bestfree[XFS_DIR2_DATA_FD_COUNT];
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dfp++) {
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if (!dfp->offset)
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return NULL;
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if (be16_to_cpu(dfp->offset) == off)
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return dfp;
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}
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/*
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* Didn't find it. This only happens if there are duplicate lengths.
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*/
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return NULL;
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}
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/*
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* Insert an unused-space entry into the bestfree table.
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*/
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xfs_dir2_data_free_t * /* entry inserted */
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xfs_dir2_data_freeinsert(
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xfs_dir2_data_hdr_t *hdr, /* data block pointer */
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xfs_dir2_data_unused_t *dup, /* unused space */
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int *loghead) /* log the data header (out) */
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{
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xfs_dir2_data_free_t *dfp; /* bestfree table pointer */
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xfs_dir2_data_free_t new; /* new bestfree entry */
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#ifdef __KERNEL__
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ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
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hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC));
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#endif
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dfp = hdr->bestfree;
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new.length = dup->length;
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new.offset = cpu_to_be16((char *)dup - (char *)hdr);
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/*
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* Insert at position 0, 1, or 2; or not at all.
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*/
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if (be16_to_cpu(new.length) > be16_to_cpu(dfp[0].length)) {
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dfp[2] = dfp[1];
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dfp[1] = dfp[0];
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dfp[0] = new;
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*loghead = 1;
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return &dfp[0];
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}
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if (be16_to_cpu(new.length) > be16_to_cpu(dfp[1].length)) {
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dfp[2] = dfp[1];
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dfp[1] = new;
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*loghead = 1;
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return &dfp[1];
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}
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if (be16_to_cpu(new.length) > be16_to_cpu(dfp[2].length)) {
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dfp[2] = new;
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*loghead = 1;
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return &dfp[2];
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}
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return NULL;
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}
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/*
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* Remove a bestfree entry from the table.
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*/
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STATIC void
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xfs_dir2_data_freeremove(
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xfs_dir2_data_hdr_t *hdr, /* data block header */
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xfs_dir2_data_free_t *dfp, /* bestfree entry pointer */
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int *loghead) /* out: log data header */
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{
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#ifdef __KERNEL__
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ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
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hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC));
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#endif
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/*
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* It's the first entry, slide the next 2 up.
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*/
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if (dfp == &hdr->bestfree[0]) {
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hdr->bestfree[0] = hdr->bestfree[1];
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hdr->bestfree[1] = hdr->bestfree[2];
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}
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/*
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* It's the second entry, slide the 3rd entry up.
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*/
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else if (dfp == &hdr->bestfree[1])
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hdr->bestfree[1] = hdr->bestfree[2];
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/*
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* Must be the last entry.
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*/
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else
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ASSERT(dfp == &hdr->bestfree[2]);
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/*
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* Clear the 3rd entry, must be zero now.
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*/
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hdr->bestfree[2].length = 0;
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hdr->bestfree[2].offset = 0;
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*loghead = 1;
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}
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/*
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* Given a data block, reconstruct its bestfree map.
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*/
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void
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xfs_dir2_data_freescan(
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xfs_mount_t *mp, /* filesystem mount point */
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xfs_dir2_data_hdr_t *hdr, /* data block header */
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int *loghead) /* out: log data header */
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{
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xfs_dir2_block_tail_t *btp; /* block tail */
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xfs_dir2_data_entry_t *dep; /* active data entry */
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xfs_dir2_data_unused_t *dup; /* unused data entry */
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char *endp; /* end of block's data */
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char *p; /* current entry pointer */
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#ifdef __KERNEL__
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ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
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hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC));
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#endif
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/*
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* Start by clearing the table.
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*/
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memset(hdr->bestfree, 0, sizeof(hdr->bestfree));
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*loghead = 1;
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/*
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* Set up pointers.
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*/
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p = (char *)(hdr + 1);
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if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)) {
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btp = xfs_dir2_block_tail_p(mp, hdr);
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endp = (char *)xfs_dir2_block_leaf_p(btp);
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} else
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endp = (char *)hdr + mp->m_dirblksize;
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/*
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* Loop over the block's entries.
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*/
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while (p < endp) {
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dup = (xfs_dir2_data_unused_t *)p;
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/*
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* If it's a free entry, insert it.
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*/
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if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
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ASSERT((char *)dup - (char *)hdr ==
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be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)));
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xfs_dir2_data_freeinsert(hdr, dup, loghead);
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p += be16_to_cpu(dup->length);
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}
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/*
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* For active entries, check their tags and skip them.
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*/
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else {
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dep = (xfs_dir2_data_entry_t *)p;
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ASSERT((char *)dep - (char *)hdr ==
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be16_to_cpu(*xfs_dir2_data_entry_tag_p(dep)));
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p += xfs_dir2_data_entsize(dep->namelen);
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}
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}
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}
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/*
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* Initialize a data block at the given block number in the directory.
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* Give back the buffer for the created block.
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*/
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int /* error */
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xfs_dir2_data_init(
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xfs_da_args_t *args, /* directory operation args */
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xfs_dir2_db_t blkno, /* logical dir block number */
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xfs_dabuf_t **bpp) /* output block buffer */
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{
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xfs_dabuf_t *bp; /* block buffer */
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xfs_dir2_data_hdr_t *hdr; /* data block header */
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xfs_inode_t *dp; /* incore directory inode */
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xfs_dir2_data_unused_t *dup; /* unused entry pointer */
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int error; /* error return value */
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int i; /* bestfree index */
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xfs_mount_t *mp; /* filesystem mount point */
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xfs_trans_t *tp; /* transaction pointer */
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int t; /* temp */
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dp = args->dp;
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mp = dp->i_mount;
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tp = args->trans;
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/*
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* Get the buffer set up for the block.
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*/
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error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, blkno), -1, &bp,
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XFS_DATA_FORK);
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if (error) {
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return error;
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}
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ASSERT(bp != NULL);
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/*
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* Initialize the header.
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*/
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hdr = bp->data;
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hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
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hdr->bestfree[0].offset = cpu_to_be16(sizeof(*hdr));
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for (i = 1; i < XFS_DIR2_DATA_FD_COUNT; i++) {
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hdr->bestfree[i].length = 0;
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hdr->bestfree[i].offset = 0;
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}
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/*
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* Set up an unused entry for the block's body.
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*/
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dup = (xfs_dir2_data_unused_t *)(hdr + 1);
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dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
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t = mp->m_dirblksize - (uint)sizeof(*hdr);
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hdr->bestfree[0].length = cpu_to_be16(t);
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dup->length = cpu_to_be16(t);
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*xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16((char *)dup - (char *)hdr);
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/*
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|
* Log it and return it.
|
|
*/
|
|
xfs_dir2_data_log_header(tp, bp);
|
|
xfs_dir2_data_log_unused(tp, bp, dup);
|
|
*bpp = bp;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Log an active data entry from the block.
|
|
*/
|
|
void
|
|
xfs_dir2_data_log_entry(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_dabuf_t *bp, /* block buffer */
|
|
xfs_dir2_data_entry_t *dep) /* data entry pointer */
|
|
{
|
|
xfs_dir2_data_hdr_t *hdr = bp->data;
|
|
|
|
ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
|
|
hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC));
|
|
|
|
xfs_da_log_buf(tp, bp, (uint)((char *)dep - (char *)hdr),
|
|
(uint)((char *)(xfs_dir2_data_entry_tag_p(dep) + 1) -
|
|
(char *)hdr - 1));
|
|
}
|
|
|
|
/*
|
|
* Log a data block header.
|
|
*/
|
|
void
|
|
xfs_dir2_data_log_header(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_dabuf_t *bp) /* block buffer */
|
|
{
|
|
xfs_dir2_data_hdr_t *hdr = bp->data;
|
|
|
|
ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
|
|
hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC));
|
|
|
|
xfs_da_log_buf(tp, bp, 0, sizeof(*hdr) - 1);
|
|
}
|
|
|
|
/*
|
|
* Log a data unused entry.
|
|
*/
|
|
void
|
|
xfs_dir2_data_log_unused(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_dabuf_t *bp, /* block buffer */
|
|
xfs_dir2_data_unused_t *dup) /* data unused pointer */
|
|
{
|
|
xfs_dir2_data_hdr_t *hdr = bp->data;
|
|
|
|
ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
|
|
hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC));
|
|
|
|
/*
|
|
* Log the first part of the unused entry.
|
|
*/
|
|
xfs_da_log_buf(tp, bp, (uint)((char *)dup - (char *)hdr),
|
|
(uint)((char *)&dup->length + sizeof(dup->length) -
|
|
1 - (char *)hdr));
|
|
/*
|
|
* Log the end (tag) of the unused entry.
|
|
*/
|
|
xfs_da_log_buf(tp, bp,
|
|
(uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr),
|
|
(uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr +
|
|
sizeof(xfs_dir2_data_off_t) - 1));
|
|
}
|
|
|
|
/*
|
|
* Make a byte range in the data block unused.
|
|
* Its current contents are unimportant.
|
|
*/
|
|
void
|
|
xfs_dir2_data_make_free(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_dabuf_t *bp, /* block buffer */
|
|
xfs_dir2_data_aoff_t offset, /* starting byte offset */
|
|
xfs_dir2_data_aoff_t len, /* length in bytes */
|
|
int *needlogp, /* out: log header */
|
|
int *needscanp) /* out: regen bestfree */
|
|
{
|
|
xfs_dir2_data_hdr_t *hdr; /* data block pointer */
|
|
xfs_dir2_data_free_t *dfp; /* bestfree pointer */
|
|
char *endptr; /* end of data area */
|
|
xfs_mount_t *mp; /* filesystem mount point */
|
|
int needscan; /* need to regen bestfree */
|
|
xfs_dir2_data_unused_t *newdup; /* new unused entry */
|
|
xfs_dir2_data_unused_t *postdup; /* unused entry after us */
|
|
xfs_dir2_data_unused_t *prevdup; /* unused entry before us */
|
|
|
|
mp = tp->t_mountp;
|
|
hdr = bp->data;
|
|
|
|
/*
|
|
* Figure out where the end of the data area is.
|
|
*/
|
|
if (hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC))
|
|
endptr = (char *)hdr + mp->m_dirblksize;
|
|
else {
|
|
xfs_dir2_block_tail_t *btp; /* block tail */
|
|
|
|
ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC));
|
|
btp = xfs_dir2_block_tail_p(mp, hdr);
|
|
endptr = (char *)xfs_dir2_block_leaf_p(btp);
|
|
}
|
|
/*
|
|
* If this isn't the start of the block, then back up to
|
|
* the previous entry and see if it's free.
|
|
*/
|
|
if (offset > sizeof(*hdr)) {
|
|
__be16 *tagp; /* tag just before us */
|
|
|
|
tagp = (__be16 *)((char *)hdr + offset) - 1;
|
|
prevdup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
|
|
if (be16_to_cpu(prevdup->freetag) != XFS_DIR2_DATA_FREE_TAG)
|
|
prevdup = NULL;
|
|
} else
|
|
prevdup = NULL;
|
|
/*
|
|
* If this isn't the end of the block, see if the entry after
|
|
* us is free.
|
|
*/
|
|
if ((char *)hdr + offset + len < endptr) {
|
|
postdup =
|
|
(xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
|
|
if (be16_to_cpu(postdup->freetag) != XFS_DIR2_DATA_FREE_TAG)
|
|
postdup = NULL;
|
|
} else
|
|
postdup = NULL;
|
|
ASSERT(*needscanp == 0);
|
|
needscan = 0;
|
|
/*
|
|
* Previous and following entries are both free,
|
|
* merge everything into a single free entry.
|
|
*/
|
|
if (prevdup && postdup) {
|
|
xfs_dir2_data_free_t *dfp2; /* another bestfree pointer */
|
|
|
|
/*
|
|
* See if prevdup and/or postdup are in bestfree table.
|
|
*/
|
|
dfp = xfs_dir2_data_freefind(hdr, prevdup);
|
|
dfp2 = xfs_dir2_data_freefind(hdr, postdup);
|
|
/*
|
|
* We need a rescan unless there are exactly 2 free entries
|
|
* namely our two. Then we know what's happening, otherwise
|
|
* since the third bestfree is there, there might be more
|
|
* entries.
|
|
*/
|
|
needscan = (hdr->bestfree[2].length != 0);
|
|
/*
|
|
* Fix up the new big freespace.
|
|
*/
|
|
be16_add_cpu(&prevdup->length, len + be16_to_cpu(postdup->length));
|
|
*xfs_dir2_data_unused_tag_p(prevdup) =
|
|
cpu_to_be16((char *)prevdup - (char *)hdr);
|
|
xfs_dir2_data_log_unused(tp, bp, prevdup);
|
|
if (!needscan) {
|
|
/*
|
|
* Has to be the case that entries 0 and 1 are
|
|
* dfp and dfp2 (don't know which is which), and
|
|
* entry 2 is empty.
|
|
* Remove entry 1 first then entry 0.
|
|
*/
|
|
ASSERT(dfp && dfp2);
|
|
if (dfp == &hdr->bestfree[1]) {
|
|
dfp = &hdr->bestfree[0];
|
|
ASSERT(dfp2 == dfp);
|
|
dfp2 = &hdr->bestfree[1];
|
|
}
|
|
xfs_dir2_data_freeremove(hdr, dfp2, needlogp);
|
|
xfs_dir2_data_freeremove(hdr, dfp, needlogp);
|
|
/*
|
|
* Now insert the new entry.
|
|
*/
|
|
dfp = xfs_dir2_data_freeinsert(hdr, prevdup, needlogp);
|
|
ASSERT(dfp == &hdr->bestfree[0]);
|
|
ASSERT(dfp->length == prevdup->length);
|
|
ASSERT(!dfp[1].length);
|
|
ASSERT(!dfp[2].length);
|
|
}
|
|
}
|
|
/*
|
|
* The entry before us is free, merge with it.
|
|
*/
|
|
else if (prevdup) {
|
|
dfp = xfs_dir2_data_freefind(hdr, prevdup);
|
|
be16_add_cpu(&prevdup->length, len);
|
|
*xfs_dir2_data_unused_tag_p(prevdup) =
|
|
cpu_to_be16((char *)prevdup - (char *)hdr);
|
|
xfs_dir2_data_log_unused(tp, bp, prevdup);
|
|
/*
|
|
* If the previous entry was in the table, the new entry
|
|
* is longer, so it will be in the table too. Remove
|
|
* the old one and add the new one.
|
|
*/
|
|
if (dfp) {
|
|
xfs_dir2_data_freeremove(hdr, dfp, needlogp);
|
|
xfs_dir2_data_freeinsert(hdr, prevdup, needlogp);
|
|
}
|
|
/*
|
|
* Otherwise we need a scan if the new entry is big enough.
|
|
*/
|
|
else {
|
|
needscan = be16_to_cpu(prevdup->length) >
|
|
be16_to_cpu(hdr->bestfree[2].length);
|
|
}
|
|
}
|
|
/*
|
|
* The following entry is free, merge with it.
|
|
*/
|
|
else if (postdup) {
|
|
dfp = xfs_dir2_data_freefind(hdr, postdup);
|
|
newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
|
|
newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
|
|
newdup->length = cpu_to_be16(len + be16_to_cpu(postdup->length));
|
|
*xfs_dir2_data_unused_tag_p(newdup) =
|
|
cpu_to_be16((char *)newdup - (char *)hdr);
|
|
xfs_dir2_data_log_unused(tp, bp, newdup);
|
|
/*
|
|
* If the following entry was in the table, the new entry
|
|
* is longer, so it will be in the table too. Remove
|
|
* the old one and add the new one.
|
|
*/
|
|
if (dfp) {
|
|
xfs_dir2_data_freeremove(hdr, dfp, needlogp);
|
|
xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
|
|
}
|
|
/*
|
|
* Otherwise we need a scan if the new entry is big enough.
|
|
*/
|
|
else {
|
|
needscan = be16_to_cpu(newdup->length) >
|
|
be16_to_cpu(hdr->bestfree[2].length);
|
|
}
|
|
}
|
|
/*
|
|
* Neither neighbor is free. Make a new entry.
|
|
*/
|
|
else {
|
|
newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
|
|
newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
|
|
newdup->length = cpu_to_be16(len);
|
|
*xfs_dir2_data_unused_tag_p(newdup) =
|
|
cpu_to_be16((char *)newdup - (char *)hdr);
|
|
xfs_dir2_data_log_unused(tp, bp, newdup);
|
|
xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
|
|
}
|
|
*needscanp = needscan;
|
|
}
|
|
|
|
/*
|
|
* Take a byte range out of an existing unused space and make it un-free.
|
|
*/
|
|
void
|
|
xfs_dir2_data_use_free(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_dabuf_t *bp, /* data block buffer */
|
|
xfs_dir2_data_unused_t *dup, /* unused entry */
|
|
xfs_dir2_data_aoff_t offset, /* starting offset to use */
|
|
xfs_dir2_data_aoff_t len, /* length to use */
|
|
int *needlogp, /* out: need to log header */
|
|
int *needscanp) /* out: need regen bestfree */
|
|
{
|
|
xfs_dir2_data_hdr_t *hdr; /* data block header */
|
|
xfs_dir2_data_free_t *dfp; /* bestfree pointer */
|
|
int matchback; /* matches end of freespace */
|
|
int matchfront; /* matches start of freespace */
|
|
int needscan; /* need to regen bestfree */
|
|
xfs_dir2_data_unused_t *newdup; /* new unused entry */
|
|
xfs_dir2_data_unused_t *newdup2; /* another new unused entry */
|
|
int oldlen; /* old unused entry's length */
|
|
|
|
hdr = bp->data;
|
|
ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
|
|
hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC));
|
|
ASSERT(be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG);
|
|
ASSERT(offset >= (char *)dup - (char *)hdr);
|
|
ASSERT(offset + len <= (char *)dup + be16_to_cpu(dup->length) - (char *)hdr);
|
|
ASSERT((char *)dup - (char *)hdr == be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)));
|
|
/*
|
|
* Look up the entry in the bestfree table.
|
|
*/
|
|
dfp = xfs_dir2_data_freefind(hdr, dup);
|
|
oldlen = be16_to_cpu(dup->length);
|
|
ASSERT(dfp || oldlen <= be16_to_cpu(hdr->bestfree[2].length));
|
|
/*
|
|
* Check for alignment with front and back of the entry.
|
|
*/
|
|
matchfront = (char *)dup - (char *)hdr == offset;
|
|
matchback = (char *)dup + oldlen - (char *)hdr == offset + len;
|
|
ASSERT(*needscanp == 0);
|
|
needscan = 0;
|
|
/*
|
|
* If we matched it exactly we just need to get rid of it from
|
|
* the bestfree table.
|
|
*/
|
|
if (matchfront && matchback) {
|
|
if (dfp) {
|
|
needscan = (hdr->bestfree[2].offset != 0);
|
|
if (!needscan)
|
|
xfs_dir2_data_freeremove(hdr, dfp, needlogp);
|
|
}
|
|
}
|
|
/*
|
|
* We match the first part of the entry.
|
|
* Make a new entry with the remaining freespace.
|
|
*/
|
|
else if (matchfront) {
|
|
newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
|
|
newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
|
|
newdup->length = cpu_to_be16(oldlen - len);
|
|
*xfs_dir2_data_unused_tag_p(newdup) =
|
|
cpu_to_be16((char *)newdup - (char *)hdr);
|
|
xfs_dir2_data_log_unused(tp, bp, newdup);
|
|
/*
|
|
* If it was in the table, remove it and add the new one.
|
|
*/
|
|
if (dfp) {
|
|
xfs_dir2_data_freeremove(hdr, dfp, needlogp);
|
|
dfp = xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
|
|
ASSERT(dfp != NULL);
|
|
ASSERT(dfp->length == newdup->length);
|
|
ASSERT(be16_to_cpu(dfp->offset) == (char *)newdup - (char *)hdr);
|
|
/*
|
|
* If we got inserted at the last slot,
|
|
* that means we don't know if there was a better
|
|
* choice for the last slot, or not. Rescan.
|
|
*/
|
|
needscan = dfp == &hdr->bestfree[2];
|
|
}
|
|
}
|
|
/*
|
|
* We match the last part of the entry.
|
|
* Trim the allocated space off the tail of the entry.
|
|
*/
|
|
else if (matchback) {
|
|
newdup = dup;
|
|
newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup);
|
|
*xfs_dir2_data_unused_tag_p(newdup) =
|
|
cpu_to_be16((char *)newdup - (char *)hdr);
|
|
xfs_dir2_data_log_unused(tp, bp, newdup);
|
|
/*
|
|
* If it was in the table, remove it and add the new one.
|
|
*/
|
|
if (dfp) {
|
|
xfs_dir2_data_freeremove(hdr, dfp, needlogp);
|
|
dfp = xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
|
|
ASSERT(dfp != NULL);
|
|
ASSERT(dfp->length == newdup->length);
|
|
ASSERT(be16_to_cpu(dfp->offset) == (char *)newdup - (char *)hdr);
|
|
/*
|
|
* If we got inserted at the last slot,
|
|
* that means we don't know if there was a better
|
|
* choice for the last slot, or not. Rescan.
|
|
*/
|
|
needscan = dfp == &hdr->bestfree[2];
|
|
}
|
|
}
|
|
/*
|
|
* Poking out the middle of an entry.
|
|
* Make two new entries.
|
|
*/
|
|
else {
|
|
newdup = dup;
|
|
newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup);
|
|
*xfs_dir2_data_unused_tag_p(newdup) =
|
|
cpu_to_be16((char *)newdup - (char *)hdr);
|
|
xfs_dir2_data_log_unused(tp, bp, newdup);
|
|
newdup2 = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
|
|
newdup2->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
|
|
newdup2->length = cpu_to_be16(oldlen - len - be16_to_cpu(newdup->length));
|
|
*xfs_dir2_data_unused_tag_p(newdup2) =
|
|
cpu_to_be16((char *)newdup2 - (char *)hdr);
|
|
xfs_dir2_data_log_unused(tp, bp, newdup2);
|
|
/*
|
|
* If the old entry was in the table, we need to scan
|
|
* if the 3rd entry was valid, since these entries
|
|
* are smaller than the old one.
|
|
* If we don't need to scan that means there were 1 or 2
|
|
* entries in the table, and removing the old and adding
|
|
* the 2 new will work.
|
|
*/
|
|
if (dfp) {
|
|
needscan = (hdr->bestfree[2].length != 0);
|
|
if (!needscan) {
|
|
xfs_dir2_data_freeremove(hdr, dfp, needlogp);
|
|
xfs_dir2_data_freeinsert(hdr, newdup, needlogp);
|
|
xfs_dir2_data_freeinsert(hdr, newdup2,
|
|
needlogp);
|
|
}
|
|
}
|
|
}
|
|
*needscanp = needscan;
|
|
}
|