/* * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. * Copyright (c) 2013 Red Hat, Inc. * All Rights Reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms 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. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include "xfs.h" #include "xfs_fs.h" #include "xfs_format.h" #include "xfs_log_format.h" #include "xfs_trans_resv.h" #include "xfs_sb.h" #include "xfs_ag.h" #include "xfs_mount.h" #include "xfs_da_format.h" #include "xfs_da_btree.h" #include "xfs_inode.h" #include "xfs_dir2.h" #include "xfs_dir2_priv.h" #include "xfs_error.h" #include "xfs_trans.h" #include "xfs_buf_item.h" #include "xfs_cksum.h" /* * Check the consistency of the data block. * The input can also be a block-format directory. * Return 0 is the buffer is good, otherwise an error. */ int __xfs_dir3_data_check( struct xfs_inode *dp, /* incore inode pointer */ struct xfs_buf *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_hdr_t *hdr; /* data block header */ 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 */ struct xfs_name name; const struct xfs_dir_ops *ops; mp = bp->b_target->bt_mount; /* * We can be passed a null dp here from a verifier, so we need to go the * hard way to get them. */ ops = xfs_dir_get_ops(mp, dp); hdr = bp->b_addr; p = (char *)ops->data_entry_p(hdr); switch (hdr->magic) { case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC): case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC): btp = xfs_dir2_block_tail_p(mp, hdr); lep = xfs_dir2_block_leaf_p(btp); endp = (char *)lep; /* * The number of leaf entries is limited by the size of the * block and the amount of space used by the data entries. * We don't know how much space is used by the data entries yet, * so just ensure that the count falls somewhere inside the * block right now. */ XFS_WANT_CORRUPTED_RETURN(be32_to_cpu(btp->count) < ((char *)btp - p) / sizeof(struct xfs_dir2_leaf_entry)); break; case cpu_to_be32(XFS_DIR3_DATA_MAGIC): case cpu_to_be32(XFS_DIR2_DATA_MAGIC): endp = (char *)hdr + mp->m_dirblksize; break; default: XFS_ERROR_REPORT("Bad Magic", XFS_ERRLEVEL_LOW, mp); return EFSCORRUPTED; } /* * Account for zero bestfree entries. */ bf = ops->data_bestfree_p(hdr); count = lastfree = freeseen = 0; if (!bf[0].length) { XFS_WANT_CORRUPTED_RETURN(!bf[0].offset); freeseen |= 1 << 0; } if (!bf[1].length) { XFS_WANT_CORRUPTED_RETURN(!bf[1].offset); freeseen |= 1 << 1; } if (!bf[2].length) { XFS_WANT_CORRUPTED_RETURN(!bf[2].offset); freeseen |= 1 << 2; } XFS_WANT_CORRUPTED_RETURN(be16_to_cpu(bf[0].length) >= be16_to_cpu(bf[1].length)); XFS_WANT_CORRUPTED_RETURN(be16_to_cpu(bf[1].length) >= be16_to_cpu(bf[2].length)); /* * 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 (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { XFS_WANT_CORRUPTED_RETURN(lastfree == 0); XFS_WANT_CORRUPTED_RETURN( be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)) == (char *)dup - (char *)hdr); dfp = xfs_dir2_data_freefind(hdr, bf, dup); if (dfp) { i = (int)(dfp - bf); XFS_WANT_CORRUPTED_RETURN( (freeseen & (1 << i)) == 0); freeseen |= 1 << i; } else { XFS_WANT_CORRUPTED_RETURN( be16_to_cpu(dup->length) <= be16_to_cpu(bf[2].length)); } p += be16_to_cpu(dup->length); 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; XFS_WANT_CORRUPTED_RETURN(dep->namelen != 0); XFS_WANT_CORRUPTED_RETURN( !xfs_dir_ino_validate(mp, be64_to_cpu(dep->inumber))); XFS_WANT_CORRUPTED_RETURN( be16_to_cpu(*ops->data_entry_tag_p(dep)) == (char *)dep - (char *)hdr); XFS_WANT_CORRUPTED_RETURN( ops->data_get_ftype(dep) < XFS_DIR3_FT_MAX); count++; lastfree = 0; if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) { addr = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk, (xfs_dir2_data_aoff_t) ((char *)dep - (char *)hdr)); name.name = dep->name; name.len = dep->namelen; hash = mp->m_dirnameops->hashname(&name); for (i = 0; i < be32_to_cpu(btp->count); i++) { if (be32_to_cpu(lep[i].address) == addr && be32_to_cpu(lep[i].hashval) == hash) break; } XFS_WANT_CORRUPTED_RETURN(i < be32_to_cpu(btp->count)); } p += ops->data_entsize(dep->namelen); } /* * Need to have seen all the entries and all the bestfree slots. */ XFS_WANT_CORRUPTED_RETURN(freeseen == 7); if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) { for (i = stale = 0; i < be32_to_cpu(btp->count); i++) { if (lep[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) stale++; if (i > 0) XFS_WANT_CORRUPTED_RETURN( be32_to_cpu(lep[i].hashval) >= be32_to_cpu(lep[i - 1].hashval)); } XFS_WANT_CORRUPTED_RETURN(count == be32_to_cpu(btp->count) - be32_to_cpu(btp->stale)); XFS_WANT_CORRUPTED_RETURN(stale == be32_to_cpu(btp->stale)); } return 0; } static bool xfs_dir3_data_verify( struct xfs_buf *bp) { struct xfs_mount *mp = bp->b_target->bt_mount; struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; if (xfs_sb_version_hascrc(&mp->m_sb)) { if (hdr3->magic != cpu_to_be32(XFS_DIR3_DATA_MAGIC)) return false; if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_uuid)) return false; if (be64_to_cpu(hdr3->blkno) != bp->b_bn) return false; } else { if (hdr3->magic != cpu_to_be32(XFS_DIR2_DATA_MAGIC)) return false; } if (__xfs_dir3_data_check(NULL, bp)) return false; return true; } /* * Readahead of the first block of the directory when it is opened is completely * oblivious to the format of the directory. Hence we can either get a block * format buffer or a data format buffer on readahead. */ static void xfs_dir3_data_reada_verify( struct xfs_buf *bp) { struct xfs_mount *mp = bp->b_target->bt_mount; struct xfs_dir2_data_hdr *hdr = bp->b_addr; switch (hdr->magic) { case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC): case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC): bp->b_ops = &xfs_dir3_block_buf_ops; bp->b_ops->verify_read(bp); return; case cpu_to_be32(XFS_DIR2_DATA_MAGIC): case cpu_to_be32(XFS_DIR3_DATA_MAGIC): xfs_dir3_data_verify(bp); return; default: XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, hdr); xfs_buf_ioerror(bp, EFSCORRUPTED); break; } } static void xfs_dir3_data_read_verify( struct xfs_buf *bp) { struct xfs_mount *mp = bp->b_target->bt_mount; if ((xfs_sb_version_hascrc(&mp->m_sb) && !xfs_buf_verify_cksum(bp, XFS_DIR3_DATA_CRC_OFF)) || !xfs_dir3_data_verify(bp)) { XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); xfs_buf_ioerror(bp, EFSCORRUPTED); } } static void xfs_dir3_data_write_verify( struct xfs_buf *bp) { struct xfs_mount *mp = bp->b_target->bt_mount; struct xfs_buf_log_item *bip = bp->b_fspriv; struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; if (!xfs_dir3_data_verify(bp)) { XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); xfs_buf_ioerror(bp, EFSCORRUPTED); return; } if (!xfs_sb_version_hascrc(&mp->m_sb)) return; if (bip) hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn); xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DIR3_DATA_CRC_OFF); } const struct xfs_buf_ops xfs_dir3_data_buf_ops = { .verify_read = xfs_dir3_data_read_verify, .verify_write = xfs_dir3_data_write_verify, }; static const struct xfs_buf_ops xfs_dir3_data_reada_buf_ops = { .verify_read = xfs_dir3_data_reada_verify, .verify_write = xfs_dir3_data_write_verify, }; int xfs_dir3_data_read( struct xfs_trans *tp, struct xfs_inode *dp, xfs_dablk_t bno, xfs_daddr_t mapped_bno, struct xfs_buf **bpp) { int err; err = xfs_da_read_buf(tp, dp, bno, mapped_bno, bpp, XFS_DATA_FORK, &xfs_dir3_data_buf_ops); if (!err && tp) xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_DATA_BUF); return err; } int xfs_dir3_data_readahead( struct xfs_trans *tp, struct xfs_inode *dp, xfs_dablk_t bno, xfs_daddr_t mapped_bno) { return xfs_da_reada_buf(tp, dp, bno, mapped_bno, XFS_DATA_FORK, &xfs_dir3_data_reada_buf_ops); } /* * 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( struct xfs_dir2_data_hdr *hdr, /* data block header */ struct xfs_dir2_data_free *bf, /* bestfree table pointer */ struct xfs_dir2_data_unused *dup) /* unused space */ { xfs_dir2_data_free_t *dfp; /* bestfree entry */ xfs_dir2_data_aoff_t off; /* offset value needed */ #ifdef DEBUG int matched; /* matched the value */ int seenzero; /* saw a 0 bestfree entry */ #endif off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr); #ifdef DEBUG /* * 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(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); for (dfp = &bf[0], seenzero = matched = 0; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) { if (!dfp->offset) { ASSERT(!dfp->length); seenzero = 1; continue; } ASSERT(seenzero == 0); if (be16_to_cpu(dfp->offset) == off) { matched = 1; ASSERT(dfp->length == dup->length); } else if (off < be16_to_cpu(dfp->offset)) ASSERT(off + be16_to_cpu(dup->length) <= be16_to_cpu(dfp->offset)); else ASSERT(be16_to_cpu(dfp->offset) + be16_to_cpu(dfp->length) <= off); ASSERT(matched || be16_to_cpu(dfp->length) >= be16_to_cpu(dup->length)); if (dfp > &bf[0]) ASSERT(be16_to_cpu(dfp[-1].length) >= be16_to_cpu(dfp[0].length)); } #endif /* * If this is smaller than the smallest bestfree entry, * it can't be there since they're sorted. */ if (be16_to_cpu(dup->length) < be16_to_cpu(bf[XFS_DIR2_DATA_FD_COUNT - 1].length)) return NULL; /* * Look at the three bestfree entries for our guy. */ for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) { if (!dfp->offset) return NULL; if (be16_to_cpu(dfp->offset) == 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( struct xfs_dir2_data_hdr *hdr, /* data block pointer */ struct xfs_dir2_data_free *dfp, /* bestfree table pointer */ struct xfs_dir2_data_unused *dup, /* unused space */ int *loghead) /* log the data header (out) */ { xfs_dir2_data_free_t new; /* new bestfree entry */ ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); new.length = dup->length; new.offset = cpu_to_be16((char *)dup - (char *)hdr); /* * Insert at position 0, 1, or 2; or not at all. */ if (be16_to_cpu(new.length) > be16_to_cpu(dfp[0].length)) { dfp[2] = dfp[1]; dfp[1] = dfp[0]; dfp[0] = new; *loghead = 1; return &dfp[0]; } if (be16_to_cpu(new.length) > be16_to_cpu(dfp[1].length)) { dfp[2] = dfp[1]; dfp[1] = new; *loghead = 1; return &dfp[1]; } if (be16_to_cpu(new.length) > be16_to_cpu(dfp[2].length)) { dfp[2] = new; *loghead = 1; return &dfp[2]; } return NULL; } /* * Remove a bestfree entry from the table. */ STATIC void xfs_dir2_data_freeremove( struct xfs_dir2_data_hdr *hdr, /* data block header */ struct xfs_dir2_data_free *bf, /* bestfree table pointer */ struct xfs_dir2_data_free *dfp, /* bestfree entry pointer */ int *loghead) /* out: log data header */ { ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); /* * It's the first entry, slide the next 2 up. */ if (dfp == &bf[0]) { bf[0] = bf[1]; bf[1] = bf[2]; } /* * It's the second entry, slide the 3rd entry up. */ else if (dfp == &bf[1]) bf[1] = bf[2]; /* * Must be the last entry. */ else ASSERT(dfp == &bf[2]); /* * Clear the 3rd entry, must be zero now. */ bf[2].length = 0; bf[2].offset = 0; *loghead = 1; } /* * Given a data block, reconstruct its bestfree map. */ void xfs_dir2_data_freescan( struct xfs_inode *dp, struct xfs_dir2_data_hdr *hdr, int *loghead) { 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 */ struct xfs_dir2_data_free *bf; char *endp; /* end of block's data */ char *p; /* current entry pointer */ ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); /* * Start by clearing the table. */ bf = dp->d_ops->data_bestfree_p(hdr); memset(bf, 0, sizeof(*bf) * XFS_DIR2_DATA_FD_COUNT); *loghead = 1; /* * Set up pointers. */ p = (char *)dp->d_ops->data_entry_p(hdr); if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) { btp = xfs_dir2_block_tail_p(dp->i_mount, hdr); endp = (char *)xfs_dir2_block_leaf_p(btp); } else endp = (char *)hdr + dp->i_mount->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 (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { ASSERT((char *)dup - (char *)hdr == be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup))); xfs_dir2_data_freeinsert(hdr, bf, dup, loghead); p += be16_to_cpu(dup->length); } /* * For active entries, check their tags and skip them. */ else { dep = (xfs_dir2_data_entry_t *)p; ASSERT((char *)dep - (char *)hdr == be16_to_cpu(*dp->d_ops->data_entry_tag_p(dep))); p += dp->d_ops->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_dir3_data_init( xfs_da_args_t *args, /* directory operation args */ xfs_dir2_db_t blkno, /* logical dir block number */ struct xfs_buf **bpp) /* output block buffer */ { struct xfs_buf *bp; /* block buffer */ xfs_dir2_data_hdr_t *hdr; /* data block header */ xfs_inode_t *dp; /* incore directory inode */ xfs_dir2_data_unused_t *dup; /* unused entry pointer */ struct xfs_dir2_data_free *bf; 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; bp->b_ops = &xfs_dir3_data_buf_ops; xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_DATA_BUF); /* * Initialize the header. */ hdr = bp->b_addr; if (xfs_sb_version_hascrc(&mp->m_sb)) { struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; memset(hdr3, 0, sizeof(*hdr3)); hdr3->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC); hdr3->blkno = cpu_to_be64(bp->b_bn); hdr3->owner = cpu_to_be64(dp->i_ino); uuid_copy(&hdr3->uuid, &mp->m_sb.sb_uuid); } else hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC); bf = dp->d_ops->data_bestfree_p(hdr); bf[0].offset = cpu_to_be16(dp->d_ops->data_entry_offset); for (i = 1; i < XFS_DIR2_DATA_FD_COUNT; i++) { bf[i].length = 0; bf[i].offset = 0; } /* * Set up an unused entry for the block's body. */ dup = dp->d_ops->data_unused_p(hdr); dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); t = mp->m_dirblksize - (uint)dp->d_ops->data_entry_offset; bf[0].length = cpu_to_be16(t); dup->length = cpu_to_be16(t); *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16((char *)dup - (char *)hdr); /* * Log it and return it. */ xfs_dir2_data_log_header(tp, dp, 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( struct xfs_trans *tp, struct xfs_inode *dp, struct xfs_buf *bp, xfs_dir2_data_entry_t *dep) /* data entry pointer */ { struct xfs_dir2_data_hdr *hdr = bp->b_addr; ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); xfs_trans_log_buf(tp, bp, (uint)((char *)dep - (char *)hdr), (uint)((char *)(dp->d_ops->data_entry_tag_p(dep) + 1) - (char *)hdr - 1)); } /* * Log a data block header. */ void xfs_dir2_data_log_header( struct xfs_trans *tp, struct xfs_inode *dp, struct xfs_buf *bp) { #ifdef DEBUG struct xfs_dir2_data_hdr *hdr = bp->b_addr; ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); #endif xfs_trans_log_buf(tp, bp, 0, dp->d_ops->data_entry_offset - 1); } /* * Log a data unused entry. */ void xfs_dir2_data_log_unused( struct xfs_trans *tp, struct xfs_buf *bp, xfs_dir2_data_unused_t *dup) /* data unused pointer */ { xfs_dir2_data_hdr_t *hdr = bp->b_addr; ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); /* * Log the first part of the unused entry. */ xfs_trans_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_trans_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( struct xfs_trans *tp, struct xfs_inode *dp, struct xfs_buf *bp, 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 */ struct xfs_dir2_data_free *bf; mp = tp->t_mountp; hdr = bp->b_addr; /* * Figure out where the end of the data area is. */ if (hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_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) || hdr->magic == cpu_to_be32(XFS_DIR3_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 > dp->d_ops->data_entry_offset) { __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. */ bf = dp->d_ops->data_bestfree_p(hdr); 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, bf, prevdup); dfp2 = xfs_dir2_data_freefind(hdr, bf, 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 = (bf[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 == &bf[1]) { dfp = &bf[0]; ASSERT(dfp2 == dfp); dfp2 = &bf[1]; } xfs_dir2_data_freeremove(hdr, bf, dfp2, needlogp); xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); /* * Now insert the new entry. */ dfp = xfs_dir2_data_freeinsert(hdr, bf, prevdup, needlogp); ASSERT(dfp == &bf[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, bf, 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, bf, dfp, needlogp); xfs_dir2_data_freeinsert(hdr, bf, prevdup, needlogp); } /* * Otherwise we need a scan if the new entry is big enough. */ else { needscan = be16_to_cpu(prevdup->length) > be16_to_cpu(bf[2].length); } } /* * The following entry is free, merge with it. */ else if (postdup) { dfp = xfs_dir2_data_freefind(hdr, bf, 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, bf, dfp, needlogp); xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp); } /* * Otherwise we need a scan if the new entry is big enough. */ else { needscan = be16_to_cpu(newdup->length) > be16_to_cpu(bf[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, bf, 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( struct xfs_trans *tp, struct xfs_inode *dp, struct xfs_buf *bp, 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 */ struct xfs_dir2_data_free *bf; hdr = bp->b_addr; ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || hdr->magic == cpu_to_be32(XFS_DIR3_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. */ oldlen = be16_to_cpu(dup->length); bf = dp->d_ops->data_bestfree_p(hdr); dfp = xfs_dir2_data_freefind(hdr, bf, dup); ASSERT(dfp || oldlen <= be16_to_cpu(bf[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 = (bf[2].offset != 0); if (!needscan) xfs_dir2_data_freeremove(hdr, bf, 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, bf, dfp, needlogp); dfp = xfs_dir2_data_freeinsert(hdr, bf, 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 == &bf[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, bf, dfp, needlogp); dfp = xfs_dir2_data_freeinsert(hdr, bf, 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 == &bf[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 = (bf[2].length != 0); if (!needscan) { xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp); xfs_dir2_data_freeinsert(hdr, bf, newdup2, needlogp); } } } *needscanp = needscan; }