diff options
Diffstat (limited to 'fs/xfs/xfs_dir2_data.c')
| -rw-r--r-- | fs/xfs/xfs_dir2_data.c | 855 |
1 files changed, 855 insertions, 0 deletions
diff --git a/fs/xfs/xfs_dir2_data.c b/fs/xfs/xfs_dir2_data.c new file mode 100644 index 000000000000..db9887a107de --- /dev/null +++ b/fs/xfs/xfs_dir2_data.c @@ -0,0 +1,855 @@ +/* + * Copyright (c) 2000-2002 Silicon Graphics, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * + * Further, this software is distributed without any warranty that it is + * free of the rightful claim of any third person regarding infringement + * or the like. Any license provided herein, whether implied or + * otherwise, applies only to this software file. Patent licenses, if + * any, provided herein do not apply to combinations of this program with + * other software, or any other product whatsoever. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write the Free Software Foundation, Inc., 59 + * Temple Place - Suite 330, Boston MA 02111-1307, USA. + * + * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy, + * Mountain View, CA 94043, or: + * + * http://www.sgi.com + * + * For further information regarding this notice, see: + * + * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/ + */ + +/* + * xfs_dir2_data.c + * Core data block handling routines for XFS V2 directories. + * See xfs_dir2_data.h for data structures. + */ + +#include "xfs.h" + +#include "xfs_macros.h" +#include "xfs_types.h" +#include "xfs_inum.h" +#include "xfs_log.h" +#include "xfs_trans.h" +#include "xfs_sb.h" +#include "xfs_dir.h" +#include "xfs_dir2.h" +#include "xfs_dmapi.h" +#include "xfs_mount.h" +#include "xfs_bmap_btree.h" +#include "xfs_attr_sf.h" +#include "xfs_dir_sf.h" +#include "xfs_dir2_sf.h" +#include "xfs_dinode.h" +#include "xfs_inode.h" +#include "xfs_da_btree.h" +#include "xfs_dir_leaf.h" +#include "xfs_dir2_data.h" +#include "xfs_dir2_leaf.h" +#include "xfs_dir2_block.h" +#include "xfs_error.h" + +#ifdef DEBUG +/* + * Check the consistency of the data block. + * The input can also be a block-format directory. + * Pop an assert if we find anything bad. + */ +void +xfs_dir2_data_check( + xfs_inode_t *dp, /* incore inode pointer */ + xfs_dabuf_t *bp) /* data block's buffer */ +{ + xfs_dir2_dataptr_t addr; /* addr for leaf lookup */ + xfs_dir2_data_free_t *bf; /* bestfree table */ + xfs_dir2_block_tail_t *btp=NULL; /* block tail */ + int count; /* count of entries found */ + xfs_dir2_data_t *d; /* data block pointer */ + xfs_dir2_data_entry_t *dep; /* data entry */ + xfs_dir2_data_free_t *dfp; /* bestfree entry */ + xfs_dir2_data_unused_t *dup; /* unused entry */ + char *endp; /* end of useful data */ + int freeseen; /* mask of bestfrees seen */ + xfs_dahash_t hash; /* hash of current name */ + int i; /* leaf index */ + int lastfree; /* last entry was unused */ + xfs_dir2_leaf_entry_t *lep=NULL; /* block leaf entries */ + xfs_mount_t *mp; /* filesystem mount point */ + char *p; /* current data position */ + int stale; /* count of stale leaves */ + + mp = dp->i_mount; + d = bp->data; + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC || + INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); + bf = d->hdr.bestfree; + p = (char *)d->u; + if (INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC) { + btp = XFS_DIR2_BLOCK_TAIL_P(mp, (xfs_dir2_block_t *)d); + lep = XFS_DIR2_BLOCK_LEAF_P(btp); + endp = (char *)lep; + } else + endp = (char *)d + mp->m_dirblksize; + count = lastfree = freeseen = 0; + /* + * Account for zero bestfree entries. + */ + if (!bf[0].length) { + ASSERT(!bf[0].offset); + freeseen |= 1 << 0; + } + if (!bf[1].length) { + ASSERT(!bf[1].offset); + freeseen |= 1 << 1; + } + if (!bf[2].length) { + ASSERT(!bf[2].offset); + freeseen |= 1 << 2; + } + ASSERT(INT_GET(bf[0].length, ARCH_CONVERT) >= INT_GET(bf[1].length, ARCH_CONVERT)); + ASSERT(INT_GET(bf[1].length, ARCH_CONVERT) >= INT_GET(bf[2].length, ARCH_CONVERT)); + /* + * Loop over the data/unused entries. + */ + while (p < endp) { + dup = (xfs_dir2_data_unused_t *)p; + /* + * If it's unused, look for the space in the bestfree table. + * If we find it, account for that, else make sure it + * doesn't need to be there. + */ + if (INT_GET(dup->freetag, ARCH_CONVERT) == XFS_DIR2_DATA_FREE_TAG) { + ASSERT(lastfree == 0); + ASSERT(INT_GET(*XFS_DIR2_DATA_UNUSED_TAG_P(dup), ARCH_CONVERT) == + (char *)dup - (char *)d); + dfp = xfs_dir2_data_freefind(d, dup); + if (dfp) { + i = (int)(dfp - bf); + ASSERT((freeseen & (1 << i)) == 0); + freeseen |= 1 << i; + } else + ASSERT(INT_GET(dup->length, ARCH_CONVERT) <= INT_GET(bf[2].length, ARCH_CONVERT)); + p += INT_GET(dup->length, ARCH_CONVERT); + lastfree = 1; + continue; + } + /* + * It's a real entry. Validate the fields. + * If this is a block directory then make sure it's + * in the leaf section of the block. + * The linear search is crude but this is DEBUG code. + */ + dep = (xfs_dir2_data_entry_t *)p; + ASSERT(dep->namelen != 0); + ASSERT(xfs_dir_ino_validate(mp, INT_GET(dep->inumber, ARCH_CONVERT)) == 0); + ASSERT(INT_GET(*XFS_DIR2_DATA_ENTRY_TAG_P(dep), ARCH_CONVERT) == + (char *)dep - (char *)d); + count++; + lastfree = 0; + if (INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC) { + addr = XFS_DIR2_DB_OFF_TO_DATAPTR(mp, mp->m_dirdatablk, + (xfs_dir2_data_aoff_t) + ((char *)dep - (char *)d)); + hash = xfs_da_hashname((char *)dep->name, dep->namelen); + for (i = 0; i < INT_GET(btp->count, ARCH_CONVERT); i++) { + if (INT_GET(lep[i].address, ARCH_CONVERT) == addr && + INT_GET(lep[i].hashval, ARCH_CONVERT) == hash) + break; + } + ASSERT(i < INT_GET(btp->count, ARCH_CONVERT)); + } + p += XFS_DIR2_DATA_ENTSIZE(dep->namelen); + } + /* + * Need to have seen all the entries and all the bestfree slots. + */ + ASSERT(freeseen == 7); + if (INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC) { + for (i = stale = 0; i < INT_GET(btp->count, ARCH_CONVERT); i++) { + if (INT_GET(lep[i].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR) + stale++; + if (i > 0) + ASSERT(INT_GET(lep[i].hashval, ARCH_CONVERT) >= INT_GET(lep[i - 1].hashval, ARCH_CONVERT)); + } + ASSERT(count == INT_GET(btp->count, ARCH_CONVERT) - INT_GET(btp->stale, ARCH_CONVERT)); + ASSERT(stale == INT_GET(btp->stale, ARCH_CONVERT)); + } +} +#endif + +/* + * Given a data block and an unused entry from that block, + * return the bestfree entry if any that corresponds to it. + */ +xfs_dir2_data_free_t * +xfs_dir2_data_freefind( + xfs_dir2_data_t *d, /* data block */ + xfs_dir2_data_unused_t *dup) /* data unused entry */ +{ + xfs_dir2_data_free_t *dfp; /* bestfree entry */ + xfs_dir2_data_aoff_t off; /* offset value needed */ +#if defined(DEBUG) && defined(__KERNEL__) + int matched; /* matched the value */ + int seenzero; /* saw a 0 bestfree entry */ +#endif + + off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)d); +#if defined(DEBUG) && defined(__KERNEL__) + /* + * Validate some consistency in the bestfree table. + * Check order, non-overlapping entries, and if we find the + * one we're looking for it has to be exact. + */ + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC || + INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); + for (dfp = &d->hdr.bestfree[0], seenzero = matched = 0; + dfp < &d->hdr.bestfree[XFS_DIR2_DATA_FD_COUNT]; + dfp++) { + if (!dfp->offset) { + ASSERT(!dfp->length); + seenzero = 1; + continue; + } + ASSERT(seenzero == 0); + if (INT_GET(dfp->offset, ARCH_CONVERT) == off) { + matched = 1; + ASSERT(INT_GET(dfp->length, ARCH_CONVERT) == INT_GET(dup->length, ARCH_CONVERT)); + } else if (off < INT_GET(dfp->offset, ARCH_CONVERT)) + ASSERT(off + INT_GET(dup->length, ARCH_CONVERT) <= INT_GET(dfp->offset, ARCH_CONVERT)); + else + ASSERT(INT_GET(dfp->offset, ARCH_CONVERT) + INT_GET(dfp->length, ARCH_CONVERT) <= off); + ASSERT(matched || INT_GET(dfp->length, ARCH_CONVERT) >= INT_GET(dup->length, ARCH_CONVERT)); + if (dfp > &d->hdr.bestfree[0]) + ASSERT(INT_GET(dfp[-1].length, ARCH_CONVERT) >= INT_GET(dfp[0].length, ARCH_CONVERT)); + } +#endif + /* + * If this is smaller than the smallest bestfree entry, + * it can't be there since they're sorted. + */ + if (INT_GET(dup->length, ARCH_CONVERT) < INT_GET(d->hdr.bestfree[XFS_DIR2_DATA_FD_COUNT - 1].length, ARCH_CONVERT)) + return NULL; + /* + * Look at the three bestfree entries for our guy. + */ + for (dfp = &d->hdr.bestfree[0]; + dfp < &d->hdr.bestfree[XFS_DIR2_DATA_FD_COUNT]; + dfp++) { + if (!dfp->offset) + return NULL; + if (INT_GET(dfp->offset, ARCH_CONVERT) == off) + return dfp; + } + /* + * Didn't find it. This only happens if there are duplicate lengths. + */ + return NULL; +} + +/* + * Insert an unused-space entry into the bestfree table. + */ +xfs_dir2_data_free_t * /* entry inserted */ +xfs_dir2_data_freeinsert( + xfs_dir2_data_t *d, /* data block pointer */ + xfs_dir2_data_unused_t *dup, /* unused space */ + int *loghead) /* log the data header (out) */ +{ + xfs_dir2_data_free_t *dfp; /* bestfree table pointer */ + xfs_dir2_data_free_t new; /* new bestfree entry */ + +#ifdef __KERNEL__ + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC || + INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); +#endif + dfp = d->hdr.bestfree; + INT_COPY(new.length, dup->length, ARCH_CONVERT); + INT_SET(new.offset, ARCH_CONVERT, (xfs_dir2_data_off_t)((char *)dup - (char *)d)); + /* + * Insert at position 0, 1, or 2; or not at all. + */ + if (INT_GET(new.length, ARCH_CONVERT) > INT_GET(dfp[0].length, ARCH_CONVERT)) { + dfp[2] = dfp[1]; + dfp[1] = dfp[0]; + dfp[0] = new; + *loghead = 1; + return &dfp[0]; + } + if (INT_GET(new.length, ARCH_CONVERT) > INT_GET(dfp[1].length, ARCH_CONVERT)) { + dfp[2] = dfp[1]; + dfp[1] = new; + *loghead = 1; + return &dfp[1]; + } + if (INT_GET(new.length, ARCH_CONVERT) > INT_GET(dfp[2].length, ARCH_CONVERT)) { + dfp[2] = new; + *loghead = 1; + return &dfp[2]; + } + return NULL; +} + +/* + * Remove a bestfree entry from the table. + */ +void +xfs_dir2_data_freeremove( + xfs_dir2_data_t *d, /* data block pointer */ + xfs_dir2_data_free_t *dfp, /* bestfree entry pointer */ + int *loghead) /* out: log data header */ +{ +#ifdef __KERNEL__ + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC || + INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); +#endif + /* + * It's the first entry, slide the next 2 up. + */ + if (dfp == &d->hdr.bestfree[0]) { + d->hdr.bestfree[0] = d->hdr.bestfree[1]; + d->hdr.bestfree[1] = d->hdr.bestfree[2]; + } + /* + * It's the second entry, slide the 3rd entry up. + */ + else if (dfp == &d->hdr.bestfree[1]) + d->hdr.bestfree[1] = d->hdr.bestfree[2]; + /* + * Must be the last entry. + */ + else + ASSERT(dfp == &d->hdr.bestfree[2]); + /* + * Clear the 3rd entry, must be zero now. + */ + d->hdr.bestfree[2].length = 0; + d->hdr.bestfree[2].offset = 0; + *loghead = 1; +} + +/* + * Given a data block, reconstruct its bestfree map. + */ +void +xfs_dir2_data_freescan( + xfs_mount_t *mp, /* filesystem mount point */ + xfs_dir2_data_t *d, /* data block pointer */ + int *loghead, /* out: log data header */ + char *aendp) /* in: caller's endp */ +{ + xfs_dir2_block_tail_t *btp; /* block tail */ + xfs_dir2_data_entry_t *dep; /* active data entry */ + xfs_dir2_data_unused_t *dup; /* unused data entry */ + char *endp; /* end of block's data */ + char *p; /* current entry pointer */ + +#ifdef __KERNEL__ + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC || + INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); +#endif + /* + * Start by clearing the table. + */ + memset(d->hdr.bestfree, 0, sizeof(d->hdr.bestfree)); + *loghead = 1; + /* + * Set up pointers. + */ + p = (char *)d->u; + if (aendp) + endp = aendp; + else if (INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC) { + btp = XFS_DIR2_BLOCK_TAIL_P(mp, (xfs_dir2_block_t *)d); + endp = (char *)XFS_DIR2_BLOCK_LEAF_P(btp); + } else + endp = (char *)d + mp->m_dirblksize; + /* + * Loop over the block's entries. + */ + while (p < endp) { + dup = (xfs_dir2_data_unused_t *)p; + /* + * If it's a free entry, insert it. + */ + if (INT_GET(dup->freetag, ARCH_CONVERT) == XFS_DIR2_DATA_FREE_TAG) { + ASSERT((char *)dup - (char *)d == + INT_GET(*XFS_DIR2_DATA_UNUSED_TAG_P(dup), ARCH_CONVERT)); + xfs_dir2_data_freeinsert(d, dup, loghead); + p += INT_GET(dup->length, ARCH_CONVERT); + } + /* + * For active entries, check their tags and skip them. + */ + else { + dep = (xfs_dir2_data_entry_t *)p; + ASSERT((char *)dep - (char *)d == + INT_GET(*XFS_DIR2_DATA_ENTRY_TAG_P(dep), ARCH_CONVERT)); + p += XFS_DIR2_DATA_ENTSIZE(dep->namelen); + } + } +} + +/* + * Initialize a data block at the given block number in the directory. + * Give back the buffer for the created block. + */ +int /* error */ +xfs_dir2_data_init( + xfs_da_args_t *args, /* directory operation args */ + xfs_dir2_db_t blkno, /* logical dir block number */ + xfs_dabuf_t **bpp) /* output block buffer */ +{ + xfs_dabuf_t *bp; /* block buffer */ + xfs_dir2_data_t *d; /* pointer to block */ + xfs_inode_t *dp; /* incore directory inode */ + xfs_dir2_data_unused_t *dup; /* unused entry pointer */ + int error; /* error return value */ + int i; /* bestfree index */ + xfs_mount_t *mp; /* filesystem mount point */ + xfs_trans_t *tp; /* transaction pointer */ + int t; /* temp */ + + dp = args->dp; + mp = dp->i_mount; + tp = args->trans; + /* + * Get the buffer set up for the block. + */ + error = xfs_da_get_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, blkno), -1, &bp, + XFS_DATA_FORK); + if (error) { + return error; + } + ASSERT(bp != NULL); + /* + * Initialize the header. + */ + d = bp->data; + INT_SET(d->hdr.magic, ARCH_CONVERT, XFS_DIR2_DATA_MAGIC); + INT_SET(d->hdr.bestfree[0].offset, ARCH_CONVERT, (xfs_dir2_data_off_t)sizeof(d->hdr)); + for (i = 1; i < XFS_DIR2_DATA_FD_COUNT; i++) { + d->hdr.bestfree[i].length = 0; + d->hdr.bestfree[i].offset = 0; + } + /* + * Set up an unused entry for the block's body. + */ + dup = &d->u[0].unused; + INT_SET(dup->freetag, ARCH_CONVERT, XFS_DIR2_DATA_FREE_TAG); + + t=mp->m_dirblksize - (uint)sizeof(d->hdr); + INT_SET(d->hdr.bestfree[0].length, ARCH_CONVERT, t); + INT_SET(dup->length, ARCH_CONVERT, t); + INT_SET(*XFS_DIR2_DATA_UNUSED_TAG_P(dup), ARCH_CONVERT, + (xfs_dir2_data_off_t)((char *)dup - (char *)d)); + /* + * 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_t *d; /* data block pointer */ + + d = bp->data; + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC || + INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); + xfs_da_log_buf(tp, bp, (uint)((char *)dep - (char *)d), + (uint)((char *)(XFS_DIR2_DATA_ENTRY_TAG_P(dep) + 1) - + (char *)d - 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_t *d; /* data block pointer */ + + d = bp->data; + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC || + INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); + xfs_da_log_buf(tp, bp, (uint)((char *)&d->hdr - (char *)d), + (uint)(sizeof(d->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_t *d; /* data block pointer */ + + d = bp->data; + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC || + INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); + /* + * Log the first part of the unused entry. + */ + xfs_da_log_buf(tp, bp, (uint)((char *)dup - (char *)d), + (uint)((char *)&dup->length + sizeof(dup->length) - + 1 - (char *)d)); + /* + * Log the end (tag) of the unused entry. + */ + xfs_da_log_buf(tp, bp, + (uint)((char *)XFS_DIR2_DATA_UNUSED_TAG_P(dup) - (char *)d), + (uint)((char *)XFS_DIR2_DATA_UNUSED_TAG_P(dup) - (char *)d + + 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_t *d; /* 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; + d = bp->data; + /* + * Figure out where the end of the data area is. + */ + if (INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC) + endptr = (char *)d + mp->m_dirblksize; + else { + xfs_dir2_block_tail_t *btp; /* block tail */ + + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); + btp = XFS_DIR2_BLOCK_TAIL_P(mp, (xfs_dir2_block_t *)d); + 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(d->hdr)) { + xfs_dir2_data_off_t *tagp; /* tag just before us */ + + tagp = (xfs_dir2_data_off_t *)((char *)d + offset) - 1; + prevdup = (xfs_dir2_data_unused_t *)((char *)d + INT_GET(*tagp, ARCH_CONVERT)); + if (INT_GET(prevdup->freetag, ARCH_CONVERT) != 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 *)d + offset + len < endptr) { + postdup = + (xfs_dir2_data_unused_t *)((char *)d + offset + len); + if (INT_GET(postdup->freetag, ARCH_CONVERT) != 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(d, prevdup); + dfp2 = xfs_dir2_data_freefind(d, 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 = d->hdr.bestfree[2].length; + /* + * Fix up the new big freespace. + */ + INT_MOD(prevdup->length, ARCH_CONVERT, len + INT_GET(postdup->length, ARCH_CONVERT)); + INT_SET(*XFS_DIR2_DATA_UNUSED_TAG_P(prevdup), ARCH_CONVERT, + (xfs_dir2_data_off_t)((char *)prevdup - (char *)d)); + 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 == &d->hdr.bestfree[1]) { + dfp = &d->hdr.bestfree[0]; + ASSERT(dfp2 == dfp); + dfp2 = &d->hdr.bestfree[1]; + } + xfs_dir2_data_freeremove(d, dfp2, needlogp); + xfs_dir2_data_freeremove(d, dfp, needlogp); + /* + * Now insert the new entry. + */ + dfp = xfs_dir2_data_freeinsert(d, prevdup, needlogp); + ASSERT(dfp == &d->hdr.bestfree[0]); + ASSERT(INT_GET(dfp->length, ARCH_CONVERT) == INT_GET(prevdup->length, ARCH_CONVERT)); + 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(d, prevdup); + INT_MOD(prevdup->length, ARCH_CONVERT, len); + INT_SET(*XFS_DIR2_DATA_UNUSED_TAG_P(prevdup), ARCH_CONVERT, + (xfs_dir2_data_off_t)((char *)prevdup - (char *)d)); + 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(d, dfp, needlogp); + (void)xfs_dir2_data_freeinsert(d, prevdup, needlogp); + } + /* + * Otherwise we need a scan if the new entry is big enough. + */ + else + needscan = INT_GET(prevdup->length, ARCH_CONVERT) > INT_GET(d->hdr.bestfree[2].length, ARCH_CONVERT); + } + /* + * The following entry is free, merge with it. + */ + else if (postdup) { + dfp = xfs_dir2_data_freefind(d, postdup); + newdup = (xfs_dir2_data_unused_t *)((char *)d + offset); + INT_SET(newdup->freetag, ARCH_CONVERT, XFS_DIR2_DATA_FREE_TAG); + INT_SET(newdup->length, ARCH_CONVERT, len + INT_GET(postdup->length, ARCH_CONVERT)); + INT_SET(*XFS_DIR2_DATA_UNUSED_TAG_P(newdup), ARCH_CONVERT, + (xfs_dir2_data_off_t)((char *)newdup - (char *)d)); + 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(d, dfp, needlogp); + (void)xfs_dir2_data_freeinsert(d, newdup, needlogp); + } + /* + * Otherwise we need a scan if the new entry is big enough. + */ + else + needscan = INT_GET(newdup->length, ARCH_CONVERT) > INT_GET(d->hdr.bestfree[2].length, ARCH_CONVERT); + } + /* + * Neither neighbor is free. Make a new entry. + */ + else { + newdup = (xfs_dir2_data_unused_t *)((char *)d + offset); + INT_SET(newdup->freetag, ARCH_CONVERT, XFS_DIR2_DATA_FREE_TAG); + INT_SET(newdup->length, ARCH_CONVERT, len); + INT_SET(*XFS_DIR2_DATA_UNUSED_TAG_P(newdup), ARCH_CONVERT, + (xfs_dir2_data_off_t)((char *)newdup - (char *)d)); + xfs_dir2_data_log_unused(tp, bp, newdup); + (void)xfs_dir2_data_freeinsert(d, 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_t *d; /* data block */ + 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 */ + + d = bp->data; + ASSERT(INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC || + INT_GET(d->hdr.magic, ARCH_CONVERT) == XFS_DIR2_BLOCK_MAGIC); + ASSERT(INT_GET(dup->freetag, ARCH_CONVERT) == XFS_DIR2_DATA_FREE_TAG); + ASSERT(offset >= (char *)dup - (char *)d); + ASSERT(offset + len <= (char *)dup + INT_GET(dup->length, ARCH_CONVERT) - (char *)d); + ASSERT((char *)dup - (char *)d == INT_GET(*XFS_DIR2_DATA_UNUSED_TAG_P(dup), ARCH_CONVERT)); + /* + * Look up the entry in the bestfree table. + */ + dfp = xfs_dir2_data_freefind(d, dup); + oldlen = INT_GET(dup->length, ARCH_CONVERT); + ASSERT(dfp || oldlen <= INT_GET(d->hdr.bestfree[2].length, ARCH_CONVERT)); + /* + * Check for alignment with front and back of the entry. + */ + matchfront = (char *)dup - (char *)d == offset; + matchback = (char *)dup + oldlen - (char *)d == 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 = d->hdr.bestfree[2].offset; + if (!needscan) + xfs_dir2_data_freeremove(d, 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 *)d + offset + len); + INT_SET(newdup->freetag, ARCH_CONVERT, XFS_DIR2_DATA_FREE_TAG); + INT_SET(newdup->length, ARCH_CONVERT, oldlen - len); + INT_SET(*XFS_DIR2_DATA_UNUSED_TAG_P(newdup), ARCH_CONVERT, + (xfs_dir2_data_off_t)((char *)newdup - (char *)d)); + 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(d, dfp, needlogp); + dfp = xfs_dir2_data_freeinsert(d, newdup, needlogp); + ASSERT(dfp != NULL); + ASSERT(INT_GET(dfp->length, ARCH_CONVERT) == INT_GET(newdup->length, ARCH_CONVERT)); + ASSERT(INT_GET(dfp->offset, ARCH_CONVERT) == (char *)newdup - (char *)d); + /* + * 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 == &d->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; + INT_SET(newdup->length, ARCH_CONVERT, (xfs_dir2_data_off_t) + (((char *)d + offset) - (char *)newdup)); + INT_SET(*XFS_DIR2_DATA_UNUSED_TAG_P(newdup), ARCH_CONVERT, + (xfs_dir2_data_off_t)((char *)newdup - (char *)d)); + 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(d, dfp, needlogp); + dfp = xfs_dir2_data_freeinsert(d, newdup, needlogp); + ASSERT(dfp != NULL); + ASSERT(INT_GET(dfp->length, ARCH_CONVERT) == INT_GET(newdup->length, ARCH_CONVERT)); + ASSERT(INT_GET(dfp->offset, ARCH_CONVERT) == (char *)newdup - (char *)d); + /* + * 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 == &d->hdr.bestfree[2]; + } + } + /* + * Poking out the middle of an entry. + * Make two new entries. + */ + else { + newdup = dup; + INT_SET(newdup->length, ARCH_CONVERT, (xfs_dir2_data_off_t) + (((char *)d + offset) - (char *)newdup)); + INT_SET(*XFS_DIR2_DATA_UNUSED_TAG_P(newdup), ARCH_CONVERT, + (xfs_dir2_data_off_t)((char *)newdup - (char *)d)); + xfs_dir2_data_log_unused(tp, bp, newdup); + newdup2 = (xfs_dir2_data_unused_t *)((char *)d + offset + len); + INT_SET(newdup2->freetag, ARCH_CONVERT, XFS_DIR2_DATA_FREE_TAG); + INT_SET(newdup2->length, ARCH_CONVERT, oldlen - len - INT_GET(newdup->length, ARCH_CONVERT)); + INT_SET(*XFS_DIR2_DATA_UNUSED_TAG_P(newdup2), ARCH_CONVERT, + (xfs_dir2_data_off_t)((char *)newdup2 - (char *)d)); + 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 = d->hdr.bestfree[2].length; + if (!needscan) { + xfs_dir2_data_freeremove(d, dfp, needlogp); + (void)xfs_dir2_data_freeinsert(d, newdup, + needlogp); + (void)xfs_dir2_data_freeinsert(d, newdup2, + needlogp); + } + } + } + *needscanp = needscan; +} |