diff options
Diffstat (limited to 'fs/xfs/libxfs/xfs_dir2_node.c')
| -rw-r--r-- | fs/xfs/libxfs/xfs_dir2_node.c | 2284 |
1 files changed, 2284 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_dir2_node.c b/fs/xfs/libxfs/xfs_dir2_node.c new file mode 100644 index 000000000000..4cf8b99d09a4 --- /dev/null +++ b/fs/xfs/libxfs/xfs_dir2_node.c @@ -0,0 +1,2284 @@ +/* + * Copyright (c) 2000-2005 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_bmap.h" +#include "xfs_dir2.h" +#include "xfs_dir2_priv.h" +#include "xfs_error.h" +#include "xfs_trace.h" +#include "xfs_trans.h" +#include "xfs_buf_item.h" +#include "xfs_cksum.h" + +/* + * Function declarations. + */ +static int xfs_dir2_leafn_add(struct xfs_buf *bp, xfs_da_args_t *args, + int index); +static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state, + xfs_da_state_blk_t *blk1, + xfs_da_state_blk_t *blk2); +static int xfs_dir2_leafn_remove(xfs_da_args_t *args, struct xfs_buf *bp, + int index, xfs_da_state_blk_t *dblk, + int *rval); +static int xfs_dir2_node_addname_int(xfs_da_args_t *args, + xfs_da_state_blk_t *fblk); + +/* + * Check internal consistency of a leafn block. + */ +#ifdef DEBUG +#define xfs_dir3_leaf_check(dp, bp) \ +do { \ + if (!xfs_dir3_leafn_check((dp), (bp))) \ + ASSERT(0); \ +} while (0); + +static bool +xfs_dir3_leafn_check( + struct xfs_inode *dp, + struct xfs_buf *bp) +{ + struct xfs_dir2_leaf *leaf = bp->b_addr; + struct xfs_dir3_icleaf_hdr leafhdr; + + dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf); + + if (leafhdr.magic == XFS_DIR3_LEAFN_MAGIC) { + struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr; + if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn) + return false; + } else if (leafhdr.magic != XFS_DIR2_LEAFN_MAGIC) + return false; + + return xfs_dir3_leaf_check_int(dp->i_mount, dp, &leafhdr, leaf); +} +#else +#define xfs_dir3_leaf_check(dp, bp) +#endif + +static bool +xfs_dir3_free_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + struct xfs_dir2_free_hdr *hdr = bp->b_addr; + + if (xfs_sb_version_hascrc(&mp->m_sb)) { + struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; + + if (hdr3->magic != cpu_to_be32(XFS_DIR3_FREE_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 (hdr->magic != cpu_to_be32(XFS_DIR2_FREE_MAGIC)) + return false; + } + + /* XXX: should bounds check the xfs_dir3_icfree_hdr here */ + + return true; +} + +static void +xfs_dir3_free_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_FREE_CRC_OFF)) + xfs_buf_ioerror(bp, EFSBADCRC); + else if (!xfs_dir3_free_verify(bp)) + xfs_buf_ioerror(bp, EFSCORRUPTED); + + if (bp->b_error) + xfs_verifier_error(bp); +} + +static void +xfs_dir3_free_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_free_verify(bp)) { + xfs_buf_ioerror(bp, EFSCORRUPTED); + xfs_verifier_error(bp); + return; + } + + if (!xfs_sb_version_hascrc(&mp->m_sb)) + return; + + if (bip) + hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn); + + xfs_buf_update_cksum(bp, XFS_DIR3_FREE_CRC_OFF); +} + +const struct xfs_buf_ops xfs_dir3_free_buf_ops = { + .verify_read = xfs_dir3_free_read_verify, + .verify_write = xfs_dir3_free_write_verify, +}; + + +static int +__xfs_dir3_free_read( + struct xfs_trans *tp, + struct xfs_inode *dp, + xfs_dablk_t fbno, + xfs_daddr_t mappedbno, + struct xfs_buf **bpp) +{ + int err; + + err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp, + XFS_DATA_FORK, &xfs_dir3_free_buf_ops); + + /* try read returns without an error or *bpp if it lands in a hole */ + if (!err && tp && *bpp) + xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_FREE_BUF); + return err; +} + +int +xfs_dir2_free_read( + struct xfs_trans *tp, + struct xfs_inode *dp, + xfs_dablk_t fbno, + struct xfs_buf **bpp) +{ + return __xfs_dir3_free_read(tp, dp, fbno, -1, bpp); +} + +static int +xfs_dir2_free_try_read( + struct xfs_trans *tp, + struct xfs_inode *dp, + xfs_dablk_t fbno, + struct xfs_buf **bpp) +{ + return __xfs_dir3_free_read(tp, dp, fbno, -2, bpp); +} + +static int +xfs_dir3_free_get_buf( + xfs_da_args_t *args, + xfs_dir2_db_t fbno, + struct xfs_buf **bpp) +{ + struct xfs_trans *tp = args->trans; + struct xfs_inode *dp = args->dp; + struct xfs_mount *mp = dp->i_mount; + struct xfs_buf *bp; + int error; + struct xfs_dir3_icfree_hdr hdr; + + error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(args->geo, fbno), + -1, &bp, XFS_DATA_FORK); + if (error) + return error; + + xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_FREE_BUF); + bp->b_ops = &xfs_dir3_free_buf_ops; + + /* + * Initialize the new block to be empty, and remember + * its first slot as our empty slot. + */ + memset(bp->b_addr, 0, sizeof(struct xfs_dir3_free_hdr)); + memset(&hdr, 0, sizeof(hdr)); + + if (xfs_sb_version_hascrc(&mp->m_sb)) { + struct xfs_dir3_free_hdr *hdr3 = bp->b_addr; + + hdr.magic = XFS_DIR3_FREE_MAGIC; + + hdr3->hdr.blkno = cpu_to_be64(bp->b_bn); + hdr3->hdr.owner = cpu_to_be64(dp->i_ino); + uuid_copy(&hdr3->hdr.uuid, &mp->m_sb.sb_uuid); + } else + hdr.magic = XFS_DIR2_FREE_MAGIC; + dp->d_ops->free_hdr_to_disk(bp->b_addr, &hdr); + *bpp = bp; + return 0; +} + +/* + * Log entries from a freespace block. + */ +STATIC void +xfs_dir2_free_log_bests( + struct xfs_da_args *args, + struct xfs_buf *bp, + int first, /* first entry to log */ + int last) /* last entry to log */ +{ + xfs_dir2_free_t *free; /* freespace structure */ + __be16 *bests; + + free = bp->b_addr; + bests = args->dp->d_ops->free_bests_p(free); + ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) || + free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC)); + xfs_trans_log_buf(args->trans, bp, + (uint)((char *)&bests[first] - (char *)free), + (uint)((char *)&bests[last] - (char *)free + + sizeof(bests[0]) - 1)); +} + +/* + * Log header from a freespace block. + */ +static void +xfs_dir2_free_log_header( + struct xfs_da_args *args, + struct xfs_buf *bp) +{ +#ifdef DEBUG + xfs_dir2_free_t *free; /* freespace structure */ + + free = bp->b_addr; + ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) || + free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC)); +#endif + xfs_trans_log_buf(args->trans, bp, 0, + args->dp->d_ops->free_hdr_size - 1); +} + +/* + * Convert a leaf-format directory to a node-format directory. + * We need to change the magic number of the leaf block, and copy + * the freespace table out of the leaf block into its own block. + */ +int /* error */ +xfs_dir2_leaf_to_node( + xfs_da_args_t *args, /* operation arguments */ + struct xfs_buf *lbp) /* leaf buffer */ +{ + xfs_inode_t *dp; /* incore directory inode */ + int error; /* error return value */ + struct xfs_buf *fbp; /* freespace buffer */ + xfs_dir2_db_t fdb; /* freespace block number */ + xfs_dir2_free_t *free; /* freespace structure */ + __be16 *from; /* pointer to freespace entry */ + int i; /* leaf freespace index */ + xfs_dir2_leaf_t *leaf; /* leaf structure */ + xfs_dir2_leaf_tail_t *ltp; /* leaf tail structure */ + xfs_mount_t *mp; /* filesystem mount point */ + int n; /* count of live freespc ents */ + xfs_dir2_data_off_t off; /* freespace entry value */ + __be16 *to; /* pointer to freespace entry */ + xfs_trans_t *tp; /* transaction pointer */ + struct xfs_dir3_icfree_hdr freehdr; + + trace_xfs_dir2_leaf_to_node(args); + + dp = args->dp; + mp = dp->i_mount; + tp = args->trans; + /* + * Add a freespace block to the directory. + */ + if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) { + return error; + } + ASSERT(fdb == xfs_dir2_byte_to_db(args->geo, XFS_DIR2_FREE_OFFSET)); + /* + * Get the buffer for the new freespace block. + */ + error = xfs_dir3_free_get_buf(args, fdb, &fbp); + if (error) + return error; + + free = fbp->b_addr; + dp->d_ops->free_hdr_from_disk(&freehdr, free); + leaf = lbp->b_addr; + ltp = xfs_dir2_leaf_tail_p(args->geo, leaf); + ASSERT(be32_to_cpu(ltp->bestcount) <= + (uint)dp->i_d.di_size / args->geo->blksize); + + /* + * Copy freespace entries from the leaf block to the new block. + * Count active entries. + */ + from = xfs_dir2_leaf_bests_p(ltp); + to = dp->d_ops->free_bests_p(free); + for (i = n = 0; i < be32_to_cpu(ltp->bestcount); i++, from++, to++) { + if ((off = be16_to_cpu(*from)) != NULLDATAOFF) + n++; + *to = cpu_to_be16(off); + } + + /* + * Now initialize the freespace block header. + */ + freehdr.nused = n; + freehdr.nvalid = be32_to_cpu(ltp->bestcount); + + dp->d_ops->free_hdr_to_disk(fbp->b_addr, &freehdr); + xfs_dir2_free_log_bests(args, fbp, 0, freehdr.nvalid - 1); + xfs_dir2_free_log_header(args, fbp); + + /* + * Converting the leaf to a leafnode is just a matter of changing the + * magic number and the ops. Do the change directly to the buffer as + * it's less work (and less code) than decoding the header to host + * format and back again. + */ + if (leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC)) + leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAFN_MAGIC); + else + leaf->hdr.info.magic = cpu_to_be16(XFS_DIR3_LEAFN_MAGIC); + lbp->b_ops = &xfs_dir3_leafn_buf_ops; + xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAFN_BUF); + xfs_dir3_leaf_log_header(args, lbp); + xfs_dir3_leaf_check(dp, lbp); + return 0; +} + +/* + * Add a leaf entry to a leaf block in a node-form directory. + * The other work necessary is done from the caller. + */ +static int /* error */ +xfs_dir2_leafn_add( + struct xfs_buf *bp, /* leaf buffer */ + xfs_da_args_t *args, /* operation arguments */ + int index) /* insertion pt for new entry */ +{ + int compact; /* compacting stale leaves */ + xfs_inode_t *dp; /* incore directory inode */ + int highstale; /* next stale entry */ + xfs_dir2_leaf_t *leaf; /* leaf structure */ + xfs_dir2_leaf_entry_t *lep; /* leaf entry */ + int lfloghigh; /* high leaf entry logging */ + int lfloglow; /* low leaf entry logging */ + int lowstale; /* previous stale entry */ + xfs_mount_t *mp; /* filesystem mount point */ + xfs_trans_t *tp; /* transaction pointer */ + struct xfs_dir3_icleaf_hdr leafhdr; + struct xfs_dir2_leaf_entry *ents; + + trace_xfs_dir2_leafn_add(args, index); + + dp = args->dp; + mp = dp->i_mount; + tp = args->trans; + leaf = bp->b_addr; + dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf); + ents = dp->d_ops->leaf_ents_p(leaf); + + /* + * Quick check just to make sure we are not going to index + * into other peoples memory + */ + if (index < 0) + return EFSCORRUPTED; + + /* + * If there are already the maximum number of leaf entries in + * the block, if there are no stale entries it won't fit. + * Caller will do a split. If there are stale entries we'll do + * a compact. + */ + + if (leafhdr.count == dp->d_ops->leaf_max_ents(args->geo)) { + if (!leafhdr.stale) + return ENOSPC; + compact = leafhdr.stale > 1; + } else + compact = 0; + ASSERT(index == 0 || be32_to_cpu(ents[index - 1].hashval) <= args->hashval); + ASSERT(index == leafhdr.count || + be32_to_cpu(ents[index].hashval) >= args->hashval); + + if (args->op_flags & XFS_DA_OP_JUSTCHECK) + return 0; + + /* + * Compact out all but one stale leaf entry. Leaves behind + * the entry closest to index. + */ + if (compact) + xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale, + &highstale, &lfloglow, &lfloghigh); + else if (leafhdr.stale) { + /* + * Set impossible logging indices for this case. + */ + lfloglow = leafhdr.count; + lfloghigh = -1; + } + + /* + * Insert the new entry, log everything. + */ + lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale, + highstale, &lfloglow, &lfloghigh); + + lep->hashval = cpu_to_be32(args->hashval); + lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(args->geo, + args->blkno, args->index)); + + dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr); + xfs_dir3_leaf_log_header(args, bp); + xfs_dir3_leaf_log_ents(args, bp, lfloglow, lfloghigh); + xfs_dir3_leaf_check(dp, bp); + return 0; +} + +#ifdef DEBUG +static void +xfs_dir2_free_hdr_check( + struct xfs_inode *dp, + struct xfs_buf *bp, + xfs_dir2_db_t db) +{ + struct xfs_dir3_icfree_hdr hdr; + + dp->d_ops->free_hdr_from_disk(&hdr, bp->b_addr); + + ASSERT((hdr.firstdb % + dp->d_ops->free_max_bests(dp->i_mount->m_dir_geo)) == 0); + ASSERT(hdr.firstdb <= db); + ASSERT(db < hdr.firstdb + hdr.nvalid); +} +#else +#define xfs_dir2_free_hdr_check(dp, bp, db) +#endif /* DEBUG */ + +/* + * Return the last hash value in the leaf. + * Stale entries are ok. + */ +xfs_dahash_t /* hash value */ +xfs_dir2_leafn_lasthash( + struct xfs_inode *dp, + struct xfs_buf *bp, /* leaf buffer */ + int *count) /* count of entries in leaf */ +{ + struct xfs_dir2_leaf *leaf = bp->b_addr; + struct xfs_dir2_leaf_entry *ents; + struct xfs_dir3_icleaf_hdr leafhdr; + + dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf); + + ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC || + leafhdr.magic == XFS_DIR3_LEAFN_MAGIC); + + if (count) + *count = leafhdr.count; + if (!leafhdr.count) + return 0; + + ents = dp->d_ops->leaf_ents_p(leaf); + return be32_to_cpu(ents[leafhdr.count - 1].hashval); +} + +/* + * Look up a leaf entry for space to add a name in a node-format leaf block. + * The extrablk in state is a freespace block. + */ +STATIC int +xfs_dir2_leafn_lookup_for_addname( + struct xfs_buf *bp, /* leaf buffer */ + xfs_da_args_t *args, /* operation arguments */ + int *indexp, /* out: leaf entry index */ + xfs_da_state_t *state) /* state to fill in */ +{ + struct xfs_buf *curbp = NULL; /* current data/free buffer */ + xfs_dir2_db_t curdb = -1; /* current data block number */ + xfs_dir2_db_t curfdb = -1; /* current free block number */ + xfs_inode_t *dp; /* incore directory inode */ + int error; /* error return value */ + int fi; /* free entry index */ + xfs_dir2_free_t *free = NULL; /* free block structure */ + int index; /* leaf entry index */ + xfs_dir2_leaf_t *leaf; /* leaf structure */ + int length; /* length of new data entry */ + xfs_dir2_leaf_entry_t *lep; /* leaf entry */ + xfs_mount_t *mp; /* filesystem mount point */ + xfs_dir2_db_t newdb; /* new data block number */ + xfs_dir2_db_t newfdb; /* new free block number */ + xfs_trans_t *tp; /* transaction pointer */ + struct xfs_dir2_leaf_entry *ents; + struct xfs_dir3_icleaf_hdr leafhdr; + + dp = args->dp; + tp = args->trans; + mp = dp->i_mount; + leaf = bp->b_addr; + dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf); + ents = dp->d_ops->leaf_ents_p(leaf); + + xfs_dir3_leaf_check(dp, bp); + ASSERT(leafhdr.count > 0); + + /* + * Look up the hash value in the leaf entries. + */ + index = xfs_dir2_leaf_search_hash(args, bp); + /* + * Do we have a buffer coming in? + */ + if (state->extravalid) { + /* If so, it's a free block buffer, get the block number. */ + curbp = state->extrablk.bp; + curfdb = state->extrablk.blkno; + free = curbp->b_addr; + ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) || + free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC)); + } + length = dp->d_ops->data_entsize(args->namelen); + /* + * Loop over leaf entries with the right hash value. + */ + for (lep = &ents[index]; + index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval; + lep++, index++) { + /* + * Skip stale leaf entries. + */ + if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR) + continue; + /* + * Pull the data block number from the entry. + */ + newdb = xfs_dir2_dataptr_to_db(args->geo, + be32_to_cpu(lep->address)); + /* + * For addname, we're looking for a place to put the new entry. + * We want to use a data block with an entry of equal + * hash value to ours if there is one with room. + * + * If this block isn't the data block we already have + * in hand, take a look at it. + */ + if (newdb != curdb) { + __be16 *bests; + + curdb = newdb; + /* + * Convert the data block to the free block + * holding its freespace information. + */ + newfdb = dp->d_ops->db_to_fdb(args->geo, newdb); + /* + * If it's not the one we have in hand, read it in. + */ + if (newfdb != curfdb) { + /* + * If we had one before, drop it. + */ + if (curbp) + xfs_trans_brelse(tp, curbp); + + error = xfs_dir2_free_read(tp, dp, + xfs_dir2_db_to_da(args->geo, + newfdb), + &curbp); + if (error) + return error; + free = curbp->b_addr; + + xfs_dir2_free_hdr_check(dp, curbp, curdb); + } + /* + * Get the index for our entry. + */ + fi = dp->d_ops->db_to_fdindex(args->geo, curdb); + /* + * If it has room, return it. + */ + bests = dp->d_ops->free_bests_p(free); + if (unlikely(bests[fi] == cpu_to_be16(NULLDATAOFF))) { + XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int", + XFS_ERRLEVEL_LOW, mp); + if (curfdb != newfdb) + xfs_trans_brelse(tp, curbp); + return EFSCORRUPTED; + } + curfdb = newfdb; + if (be16_to_cpu(bests[fi]) >= length) + goto out; + } + } + /* Didn't find any space */ + fi = -1; +out: + ASSERT(args->op_flags & XFS_DA_OP_OKNOENT); + if (curbp) { + /* Giving back a free block. */ + state->extravalid = 1; + state->extrablk.bp = curbp; + state->extrablk.index = fi; + state->extrablk.blkno = curfdb; + + /* + * Important: this magic number is not in the buffer - it's for + * buffer type information and therefore only the free/data type + * matters here, not whether CRCs are enabled or not. + */ + state->extrablk.magic = XFS_DIR2_FREE_MAGIC; + } else { + state->extravalid = 0; + } + /* + * Return the index, that will be the insertion point. + */ + *indexp = index; + return ENOENT; +} + +/* + * Look up a leaf entry in a node-format leaf block. + * The extrablk in state a data block. + */ +STATIC int +xfs_dir2_leafn_lookup_for_entry( + struct xfs_buf *bp, /* leaf buffer */ + xfs_da_args_t *args, /* operation arguments */ + int *indexp, /* out: leaf entry index */ + xfs_da_state_t *state) /* state to fill in */ +{ + struct xfs_buf *curbp = NULL; /* current data/free buffer */ + xfs_dir2_db_t curdb = -1; /* current data block number */ + xfs_dir2_data_entry_t *dep; /* data block entry */ + xfs_inode_t *dp; /* incore directory inode */ + int error; /* error return value */ + int index; /* leaf entry index */ + xfs_dir2_leaf_t *leaf; /* leaf structure */ + xfs_dir2_leaf_entry_t *lep; /* leaf entry */ + xfs_mount_t *mp; /* filesystem mount point */ + xfs_dir2_db_t newdb; /* new data block number */ + xfs_trans_t *tp; /* transaction pointer */ + enum xfs_dacmp cmp; /* comparison result */ + struct xfs_dir2_leaf_entry *ents; + struct xfs_dir3_icleaf_hdr leafhdr; + + dp = args->dp; + tp = args->trans; + mp = dp->i_mount; + leaf = bp->b_addr; + dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf); + ents = dp->d_ops->leaf_ents_p(leaf); + + xfs_dir3_leaf_check(dp, bp); + ASSERT(leafhdr.count > 0); + + /* + * Look up the hash value in the leaf entries. + */ + index = xfs_dir2_leaf_search_hash(args, bp); + /* + * Do we have a buffer coming in? + */ + if (state->extravalid) { + curbp = state->extrablk.bp; + curdb = state->extrablk.blkno; + } + /* + * Loop over leaf entries with the right hash value. + */ + for (lep = &ents[index]; + index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval; + lep++, index++) { + /* + * Skip stale leaf entries. + */ + if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR) + continue; + /* + * Pull the data block number from the entry. + */ + newdb = xfs_dir2_dataptr_to_db(args->geo, + be32_to_cpu(lep->address)); + /* + * Not adding a new entry, so we really want to find + * the name given to us. + * + * If it's a different data block, go get it. + */ + if (newdb != curdb) { + /* + * If we had a block before that we aren't saving + * for a CI name, drop it + */ + if (curbp && (args->cmpresult == XFS_CMP_DIFFERENT || + curdb != state->extrablk.blkno)) + xfs_trans_brelse(tp, curbp); + /* + * If needing the block that is saved with a CI match, + * use it otherwise read in the new data block. + */ + if (args->cmpresult != XFS_CMP_DIFFERENT && + newdb == state->extrablk.blkno) { + ASSERT(state->extravalid); + curbp = state->extrablk.bp; + } else { + error = xfs_dir3_data_read(tp, dp, + xfs_dir2_db_to_da(args->geo, + newdb), + -1, &curbp); + if (error) + return error; + } + xfs_dir3_data_check(dp, curbp); + curdb = newdb; + } + /* + * Point to the data entry. + */ + dep = (xfs_dir2_data_entry_t *)((char *)curbp->b_addr + + xfs_dir2_dataptr_to_off(args->geo, + be32_to_cpu(lep->address))); + /* + * Compare the entry and if it's an exact match, return + * EEXIST immediately. If it's the first case-insensitive + * match, store the block & inode number and continue looking. + */ + cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen); + if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) { + /* If there is a CI match block, drop it */ + if (args->cmpresult != XFS_CMP_DIFFERENT && + curdb != state->extrablk.blkno) + xfs_trans_brelse(tp, state->extrablk.bp); + args->cmpresult = cmp; + args->inumber = be64_to_cpu(dep->inumber); + args->filetype = dp->d_ops->data_get_ftype(dep); + *indexp = index; + state->extravalid = 1; + state->extrablk.bp = curbp; + state->extrablk.blkno = curdb; + state->extrablk.index = (int)((char *)dep - + (char *)curbp->b_addr); + state->extrablk.magic = XFS_DIR2_DATA_MAGIC; + curbp->b_ops = &xfs_dir3_data_buf_ops; + xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF); + if (cmp == XFS_CMP_EXACT) + return EEXIST; + } + } + ASSERT(index == leafhdr.count || (args->op_flags & XFS_DA_OP_OKNOENT)); + if (curbp) { + if (args->cmpresult == XFS_CMP_DIFFERENT) { + /* Giving back last used data block. */ + state->extravalid = 1; + state->extrablk.bp = curbp; + state->extrablk.index = -1; + state->extrablk.blkno = curdb; + state->extrablk.magic = XFS_DIR2_DATA_MAGIC; + curbp->b_ops = &xfs_dir3_data_buf_ops; + xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF); + } else { + /* If the curbp is not the CI match block, drop it */ + if (state->extrablk.bp != curbp) + xfs_trans_brelse(tp, curbp); + } + } else { + state->extravalid = 0; + } + *indexp = index; + return ENOENT; +} + +/* + * Look up a leaf entry in a node-format leaf block. + * If this is an addname then the extrablk in state is a freespace block, + * otherwise it's a data block. + */ +int +xfs_dir2_leafn_lookup_int( + struct xfs_buf *bp, /* leaf buffer */ + xfs_da_args_t *args, /* operation arguments */ + int *indexp, /* out: leaf entry index */ + xfs_da_state_t *state) /* state to fill in */ +{ + if (args->op_flags & XFS_DA_OP_ADDNAME) + return xfs_dir2_leafn_lookup_for_addname(bp, args, indexp, + state); + return xfs_dir2_leafn_lookup_for_entry(bp, args, indexp, state); +} + +/* + * Move count leaf entries from source to destination leaf. + * Log entries and headers. Stale entries are preserved. + */ +static void +xfs_dir3_leafn_moveents( + xfs_da_args_t *args, /* operation arguments */ + struct xfs_buf *bp_s, /* source */ + struct xfs_dir3_icleaf_hdr *shdr, + struct xfs_dir2_leaf_entry *sents, + int start_s,/* source leaf index */ + struct xfs_buf *bp_d, /* destination */ + struct xfs_dir3_icleaf_hdr *dhdr, + struct xfs_dir2_leaf_entry *dents, + int start_d,/* destination leaf index */ + int count) /* count of leaves to copy */ +{ + int stale; /* count stale leaves copied */ + + trace_xfs_dir2_leafn_moveents(args, start_s, start_d, count); + + /* + * Silently return if nothing to do. + */ + if (count == 0) + return; + + /* + * If the destination index is not the end of the current + * destination leaf entries, open up a hole in the destination + * to hold the new entries. + */ + if (start_d < dhdr->count) { + memmove(&dents[start_d + count], &dents[start_d], + (dhdr->count - start_d) * sizeof(xfs_dir2_leaf_entry_t)); + xfs_dir3_leaf_log_ents(args, bp_d, start_d + count, + count + dhdr->count - 1); + } + /* + * If the source has stale leaves, count the ones in the copy range + * so we can update the header correctly. + */ + if (shdr->stale) { + int i; /* temp leaf index */ + + for (i = start_s, stale = 0; i < start_s + count; i++) { + if (sents[i].address == + cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) + stale++; + } + } else + stale = 0; + /* + * Copy the leaf entries from source to destination. + */ + memcpy(&dents[start_d], &sents[start_s], + count * sizeof(xfs_dir2_leaf_entry_t)); + xfs_dir3_leaf_log_ents(args, bp_d, start_d, start_d + count - 1); + + /* + * If there are source entries after the ones we copied, + * delete the ones we copied by sliding the next ones down. + */ + if (start_s + count < shdr->count) { + memmove(&sents[start_s], &sents[start_s + count], + count * sizeof(xfs_dir2_leaf_entry_t)); + xfs_dir3_leaf_log_ents(args, bp_s, start_s, start_s + count - 1); + } + + /* + * Update the headers and log them. + */ + shdr->count -= count; + shdr->stale -= stale; + dhdr->count += count; + dhdr->stale += stale; +} + +/* + * Determine the sort order of two leaf blocks. + * Returns 1 if both are valid and leaf2 should be before leaf1, else 0. + */ +int /* sort order */ +xfs_dir2_leafn_order( + struct xfs_inode *dp, + struct xfs_buf *leaf1_bp, /* leaf1 buffer */ + struct xfs_buf *leaf2_bp) /* leaf2 buffer */ +{ + struct xfs_dir2_leaf *leaf1 = leaf1_bp->b_addr; + struct xfs_dir2_leaf *leaf2 = leaf2_bp->b_addr; + struct xfs_dir2_leaf_entry *ents1; + struct xfs_dir2_leaf_entry *ents2; + struct xfs_dir3_icleaf_hdr hdr1; + struct xfs_dir3_icleaf_hdr hdr2; + + dp->d_ops->leaf_hdr_from_disk(&hdr1, leaf1); + dp->d_ops->leaf_hdr_from_disk(&hdr2, leaf2); + ents1 = dp->d_ops->leaf_ents_p(leaf1); + ents2 = dp->d_ops->leaf_ents_p(leaf2); + + if (hdr1.count > 0 && hdr2.count > 0 && + (be32_to_cpu(ents2[0].hashval) < be32_to_cpu(ents1[0].hashval) || + be32_to_cpu(ents2[hdr2.count - 1].hashval) < + be32_to_cpu(ents1[hdr1.count - 1].hashval))) + return 1; + return 0; +} + +/* + * Rebalance leaf entries between two leaf blocks. + * This is actually only called when the second block is new, + * though the code deals with the general case. + * A new entry will be inserted in one of the blocks, and that + * entry is taken into account when balancing. + */ +static void +xfs_dir2_leafn_rebalance( + xfs_da_state_t *state, /* btree cursor */ + xfs_da_state_blk_t *blk1, /* first btree block */ + xfs_da_state_blk_t *blk2) /* second btree block */ +{ + xfs_da_args_t *args; /* operation arguments */ + int count; /* count (& direction) leaves */ + int isleft; /* new goes in left leaf */ + xfs_dir2_leaf_t *leaf1; /* first leaf structure */ + xfs_dir2_leaf_t *leaf2; /* second leaf structure */ + int mid; /* midpoint leaf index */ +#if defined(DEBUG) || defined(XFS_WARN) + int oldstale; /* old count of stale leaves */ +#endif + int oldsum; /* old total leaf count */ + int swap; /* swapped leaf blocks */ + struct xfs_dir2_leaf_entry *ents1; + struct xfs_dir2_leaf_entry *ents2; + struct xfs_dir3_icleaf_hdr hdr1; + struct xfs_dir3_icleaf_hdr hdr2; + struct xfs_inode *dp = state->args->dp; + + args = state->args; + /* + * If the block order is wrong, swap the arguments. + */ + if ((swap = xfs_dir2_leafn_order(dp, blk1->bp, blk2->bp))) { + xfs_da_state_blk_t *tmp; /* temp for block swap */ + + tmp = blk1; + blk1 = blk2; + blk2 = tmp; + } + leaf1 = blk1->bp->b_addr; + leaf2 = blk2->bp->b_addr; + dp->d_ops->leaf_hdr_from_disk(&hdr1, leaf1); + dp->d_ops->leaf_hdr_from_disk(&hdr2, leaf2); + ents1 = dp->d_ops->leaf_ents_p(leaf1); + ents2 = dp->d_ops->leaf_ents_p(leaf2); + + oldsum = hdr1.count + hdr2.count; +#if defined(DEBUG) || defined(XFS_WARN) + oldstale = hdr1.stale + hdr2.stale; +#endif + mid = oldsum >> 1; + + /* + * If the old leaf count was odd then the new one will be even, + * so we need to divide the new count evenly. + */ + if (oldsum & 1) { + xfs_dahash_t midhash; /* middle entry hash value */ + + if (mid >= hdr1.count) + midhash = be32_to_cpu(ents2[mid - hdr1.count].hashval); + else + midhash = be32_to_cpu(ents1[mid].hashval); + isleft = args->hashval <= midhash; + } + /* + * If the old count is even then the new count is odd, so there's + * no preferred side for the new entry. + * Pick the left one. + */ + else + isleft = 1; + /* + * Calculate moved entry count. Positive means left-to-right, + * negative means right-to-left. Then move the entries. + */ + count = hdr1.count - mid + (isleft == 0); + if (count > 0) + xfs_dir3_leafn_moveents(args, blk1->bp, &hdr1, ents1, + hdr1.count - count, blk2->bp, + &hdr2, ents2, 0, count); + else if (count < 0) + xfs_dir3_leafn_moveents(args, blk2->bp, &hdr2, ents2, 0, + blk1->bp, &hdr1, ents1, + hdr1.count, count); + + ASSERT(hdr1.count + hdr2.count == oldsum); + ASSERT(hdr1.stale + hdr2.stale == oldstale); + + /* log the changes made when moving the entries */ + dp->d_ops->leaf_hdr_to_disk(leaf1, &hdr1); + dp->d_ops->leaf_hdr_to_disk(leaf2, &hdr2); + xfs_dir3_leaf_log_header(args, blk1->bp); + xfs_dir3_leaf_log_header(args, blk2->bp); + + xfs_dir3_leaf_check(dp, blk1->bp); + xfs_dir3_leaf_check(dp, blk2->bp); + + /* + * Mark whether we're inserting into the old or new leaf. + */ + if (hdr1.count < hdr2.count) + state->inleaf = swap; + else if (hdr1.count > hdr2.count) + state->inleaf = !swap; + else + state->inleaf = swap ^ (blk1->index <= hdr1.count); + /* + * Adjust the expected index for insertion. + */ + if (!state->inleaf) + blk2->index = blk1->index - hdr1.count; + + /* + * Finally sanity check just to make sure we are not returning a + * negative index + */ + if (blk2->index < 0) { + state->inleaf = 1; + blk2->index = 0; + xfs_alert(dp->i_mount, + "%s: picked the wrong leaf? reverting original leaf: blk1->index %d", + __func__, blk1->index); + } +} + +static int +xfs_dir3_data_block_free( + xfs_da_args_t *args, + struct xfs_dir2_data_hdr *hdr, + struct xfs_dir2_free *free, + xfs_dir2_db_t fdb, + int findex, + struct xfs_buf *fbp, + int longest) +{ + int logfree = 0; + __be16 *bests; + struct xfs_dir3_icfree_hdr freehdr; + struct xfs_inode *dp = args->dp; + + dp->d_ops->free_hdr_from_disk(&freehdr, free); + bests = dp->d_ops->free_bests_p(free); + if (hdr) { + /* + * Data block is not empty, just set the free entry to the new + * value. + */ + bests[findex] = cpu_to_be16(longest); + xfs_dir2_free_log_bests(args, fbp, findex, findex); + return 0; + } + + /* One less used entry in the free table. */ + freehdr.nused--; + + /* + * If this was the last entry in the table, we can trim the table size + * back. There might be other entries at the end referring to + * non-existent data blocks, get those too. + */ + if (findex == freehdr.nvalid - 1) { + int i; /* free entry index */ + + for (i = findex - 1; i >= 0; i--) { + if (bests[i] != cpu_to_be16(NULLDATAOFF)) + break; + } + freehdr.nvalid = i + 1; + logfree = 0; + } else { + /* Not the last entry, just punch it out. */ + bests[findex] = cpu_to_be16(NULLDATAOFF); + logfree = 1; + } + + dp->d_ops->free_hdr_to_disk(free, &freehdr); + xfs_dir2_free_log_header(args, fbp); + + /* + * If there are no useful entries left in the block, get rid of the + * block if we can. + */ + if (!freehdr.nused) { + int error; + + error = xfs_dir2_shrink_inode(args, fdb, fbp); + if (error == 0) { + fbp = NULL; + logfree = 0; + } else if (error != ENOSPC || args->total != 0) + return error; + /* + * It's possible to get ENOSPC if there is no + * space reservation. In this case some one + * else will eventually get rid of this block. + */ + } + + /* Log the free entry that changed, unless we got rid of it. */ + if (logfree) + xfs_dir2_free_log_bests(args, fbp, findex, findex); + return 0; +} + +/* + * Remove an entry from a node directory. + * This removes the leaf entry and the data entry, + * and updates the free block if necessary. + */ +static int /* error */ +xfs_dir2_leafn_remove( + xfs_da_args_t *args, /* operation arguments */ + struct xfs_buf *bp, /* leaf buffer */ + int index, /* leaf entry index */ + xfs_da_state_blk_t *dblk, /* data block */ + int *rval) /* resulting block needs join */ +{ + xfs_dir2_data_hdr_t *hdr; /* data block header */ + xfs_dir2_db_t db; /* data block number */ + struct xfs_buf *dbp; /* data block buffer */ + xfs_dir2_data_entry_t *dep; /* data block entry */ + xfs_inode_t *dp; /* incore directory inode */ + xfs_dir2_leaf_t *leaf; /* leaf structure */ + xfs_dir2_leaf_entry_t *lep; /* leaf entry */ + int longest; /* longest data free entry */ + int off; /* data block entry offset */ + xfs_mount_t *mp; /* filesystem mount point */ + int needlog; /* need to log data header */ + int needscan; /* need to rescan data frees */ + xfs_trans_t *tp; /* transaction pointer */ + struct xfs_dir2_data_free *bf; /* bestfree table */ + struct xfs_dir3_icleaf_hdr leafhdr; + struct xfs_dir2_leaf_entry *ents; + + trace_xfs_dir2_leafn_remove(args, index); + + dp = args->dp; + tp = args->trans; + mp = dp->i_mount; + leaf = bp->b_addr; + dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf); + ents = dp->d_ops->leaf_ents_p(leaf); + + /* + * Point to the entry we're removing. + */ + lep = &ents[index]; + + /* + * Extract the data block and offset from the entry. + */ + db = xfs_dir2_dataptr_to_db(args->geo, be32_to_cpu(lep->address)); + ASSERT(dblk->blkno == db); + off = xfs_dir2_dataptr_to_off(args->geo, be32_to_cpu(lep->address)); + ASSERT(dblk->index == off); + + /* + * Kill the leaf entry by marking it stale. + * Log the leaf block changes. + */ + leafhdr.stale++; + dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr); + xfs_dir3_leaf_log_header(args, bp); + + lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR); + xfs_dir3_leaf_log_ents(args, bp, index, index); + + /* + * Make the data entry free. Keep track of the longest freespace + * in the data block in case it changes. + */ + dbp = dblk->bp; + hdr = dbp->b_addr; + dep = (xfs_dir2_data_entry_t *)((char *)hdr + off); + bf = dp->d_ops->data_bestfree_p(hdr); + longest = be16_to_cpu(bf[0].length); + needlog = needscan = 0; + xfs_dir2_data_make_free(args, dbp, off, + dp->d_ops->data_entsize(dep->namelen), &needlog, &needscan); + /* + * Rescan the data block freespaces for bestfree. + * Log the data block header if needed. + */ + if (needscan) + xfs_dir2_data_freescan(dp, hdr, &needlog); + if (needlog) + xfs_dir2_data_log_header(args, dbp); + xfs_dir3_data_check(dp, dbp); + /* + * If the longest data block freespace changes, need to update + * the corresponding freeblock entry. + */ + if (longest < be16_to_cpu(bf[0].length)) { + int error; /* error return value */ + struct xfs_buf *fbp; /* freeblock buffer */ + xfs_dir2_db_t fdb; /* freeblock block number */ + int findex; /* index in freeblock entries */ + xfs_dir2_free_t *free; /* freeblock structure */ + + /* + * Convert the data block number to a free block, + * read in the free block. + */ + fdb = dp->d_ops->db_to_fdb(args->geo, db); + error = xfs_dir2_free_read(tp, dp, + xfs_dir2_db_to_da(args->geo, fdb), + &fbp); + if (error) + return error; + free = fbp->b_addr; +#ifdef DEBUG + { + struct xfs_dir3_icfree_hdr freehdr; + dp->d_ops->free_hdr_from_disk(&freehdr, free); + ASSERT(freehdr.firstdb == dp->d_ops->free_max_bests(args->geo) * + (fdb - xfs_dir2_byte_to_db(args->geo, + XFS_DIR2_FREE_OFFSET))); + } +#endif + /* + * Calculate which entry we need to fix. + */ + findex = dp->d_ops->db_to_fdindex(args->geo, db); + longest = be16_to_cpu(bf[0].length); + /* + * If the data block is now empty we can get rid of it + * (usually). + */ + if (longest == args->geo->blksize - + dp->d_ops->data_entry_offset) { + /* + * Try to punch out the data block. + */ + error = xfs_dir2_shrink_inode(args, db, dbp); + if (error == 0) { + dblk->bp = NULL; + hdr = NULL; + } + /* + * We can get ENOSPC if there's no space reservation. + * In this case just drop the buffer and some one else + * will eventually get rid of the empty block. + */ + else if (!(error == ENOSPC && args->total == 0)) + return error; + } + /* + * If we got rid of the data block, we can eliminate that entry + * in the free block. + */ + error = xfs_dir3_data_block_free(args, hdr, free, + fdb, findex, fbp, longest); + if (error) + return error; + } + + xfs_dir3_leaf_check(dp, bp); + /* + * Return indication of whether this leaf block is empty enough + * to justify trying to join it with a neighbor. + */ + *rval = (dp->d_ops->leaf_hdr_size + + (uint)sizeof(ents[0]) * (leafhdr.count - leafhdr.stale)) < + args->geo->magicpct; + return 0; +} + +/* + * Split the leaf entries in the old block into old and new blocks. + */ +int /* error */ +xfs_dir2_leafn_split( + xfs_da_state_t *state, /* btree cursor */ + xfs_da_state_blk_t *oldblk, /* original block */ + xfs_da_state_blk_t *newblk) /* newly created block */ +{ + xfs_da_args_t *args; /* operation arguments */ + xfs_dablk_t blkno; /* new leaf block number */ + int error; /* error return value */ + xfs_mount_t *mp; /* filesystem mount point */ + struct xfs_inode *dp; + + /* + * Allocate space for a new leaf node. + */ + args = state->args; + dp = args->dp; + mp = dp->i_mount; + ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC); + error = xfs_da_grow_inode(args, &blkno); + if (error) { + return error; + } + /* + * Initialize the new leaf block. + */ + error = xfs_dir3_leaf_get_buf(args, xfs_dir2_da_to_db(args->geo, blkno), + &newblk->bp, XFS_DIR2_LEAFN_MAGIC); + if (error) + return error; + + newblk->blkno = blkno; + newblk->magic = XFS_DIR2_LEAFN_MAGIC; + /* + * Rebalance the entries across the two leaves, link the new + * block into the leaves. + */ + xfs_dir2_leafn_rebalance(state, oldblk, newblk); + error = xfs_da3_blk_link(state, oldblk, newblk); + if (error) { + return error; + } + /* + * Insert the new entry in the correct block. + */ + if (state->inleaf) + error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index); + else + error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index); + /* + * Update last hashval in each block since we added the name. + */ + oldblk->hashval = xfs_dir2_leafn_lasthash(dp, oldblk->bp, NULL); + newblk->hashval = xfs_dir2_leafn_lasthash(dp, newblk->bp, NULL); + xfs_dir3_leaf_check(dp, oldblk->bp); + xfs_dir3_leaf_check(dp, newblk->bp); + return error; +} + +/* + * Check a leaf block and its neighbors to see if the block should be + * collapsed into one or the other neighbor. Always keep the block + * with the smaller block number. + * If the current block is over 50% full, don't try to join it, return 0. + * If the block is empty, fill in the state structure and return 2. + * If it can be collapsed, fill in the state structure and return 1. + * If nothing can be done, return 0. + */ +int /* error */ +xfs_dir2_leafn_toosmall( + xfs_da_state_t *state, /* btree cursor */ + int *action) /* resulting action to take */ +{ + xfs_da_state_blk_t *blk; /* leaf block */ + xfs_dablk_t blkno; /* leaf block number */ + struct xfs_buf *bp; /* leaf buffer */ + int bytes; /* bytes in use */ + int count; /* leaf live entry count */ + int error; /* error return value */ + int forward; /* sibling block direction */ + int i; /* sibling counter */ + xfs_dir2_leaf_t *leaf; /* leaf structure */ + int rval; /* result from path_shift */ + struct xfs_dir3_icleaf_hdr leafhdr; + struct xfs_dir2_leaf_entry *ents; + struct xfs_inode *dp = state->args->dp; + + /* + * Check for the degenerate case of the block being over 50% full. + * If so, it's not worth even looking to see if we might be able + * to coalesce with a sibling. + */ + blk = &state->path.blk[state->path.active - 1]; + leaf = blk->bp->b_addr; + dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf); + ents = dp->d_ops->leaf_ents_p(leaf); + xfs_dir3_leaf_check(dp, blk->bp); + + count = leafhdr.count - leafhdr.stale; + bytes = dp->d_ops->leaf_hdr_size + count * sizeof(ents[0]); + if (bytes > (state->args->geo->blksize >> 1)) { + /* + * Blk over 50%, don't try to join. + */ + *action = 0; + return 0; + } + /* + * Check for the degenerate case of the block being empty. + * If the block is empty, we'll simply delete it, no need to + * coalesce it with a sibling block. We choose (arbitrarily) + * to merge with the forward block unless it is NULL. + */ + if (count == 0) { + /* + * Make altpath point to the block we want to keep and + * path point to the block we want to drop (this one). + */ + forward = (leafhdr.forw != 0); + memcpy(&state->altpath, &state->path, sizeof(state->path)); + error = xfs_da3_path_shift(state, &state->altpath, forward, 0, + &rval); + if (error) + return error; + *action = rval ? 2 : 0; + return 0; + } + /* + * Examine each sibling block to see if we can coalesce with + * at least 25% free space to spare. We need to figure out + * whether to merge with the forward or the backward block. + * We prefer coalescing with the lower numbered sibling so as + * to shrink a directory over time. + */ + forward = leafhdr.forw < leafhdr.back; + for (i = 0, bp = NULL; i < 2; forward = !forward, i++) { + struct xfs_dir3_icleaf_hdr hdr2; + + blkno = forward ? leafhdr.forw : leafhdr.back; + if (blkno == 0) + continue; + /* + * Read the sibling leaf block. + */ + error = xfs_dir3_leafn_read(state->args->trans, dp, + blkno, -1, &bp); + if (error) + return error; + + /* + * Count bytes in the two blocks combined. + */ + count = leafhdr.count - leafhdr.stale; + bytes = state->args->geo->blksize - + (state->args->geo->blksize >> 2); + + leaf = bp->b_addr; + dp->d_ops->leaf_hdr_from_disk(&hdr2, leaf); + ents = dp->d_ops->leaf_ents_p(leaf); + count += hdr2.count - hdr2.stale; + bytes -= count * sizeof(ents[0]); + + /* + * Fits with at least 25% to spare. + */ + if (bytes >= 0) + break; + xfs_trans_brelse(state->args->trans, bp); + } + /* + * Didn't like either block, give up. + */ + if (i >= 2) { + *action = 0; + return 0; + } + + /* + * Make altpath point to the block we want to keep (the lower + * numbered block) and path point to the block we want to drop. + */ + memcpy(&state->altpath, &state->path, sizeof(state->path)); + if (blkno < blk->blkno) + error = xfs_da3_path_shift(state, &state->altpath, forward, 0, + &rval); + else + error = xfs_da3_path_shift(state, &state->path, forward, 0, + &rval); + if (error) { + return error; + } + *action = rval ? 0 : 1; + return 0; +} + +/* + * Move all the leaf entries from drop_blk to save_blk. + * This is done as part of a join operation. + */ +void +xfs_dir2_leafn_unbalance( + xfs_da_state_t *state, /* cursor */ + xfs_da_state_blk_t *drop_blk, /* dead block */ + xfs_da_state_blk_t *save_blk) /* surviving block */ +{ + xfs_da_args_t *args; /* operation arguments */ + xfs_dir2_leaf_t *drop_leaf; /* dead leaf structure */ + xfs_dir2_leaf_t *save_leaf; /* surviving leaf structure */ + struct xfs_dir3_icleaf_hdr savehdr; + struct xfs_dir3_icleaf_hdr drophdr; + struct xfs_dir2_leaf_entry *sents; + struct xfs_dir2_leaf_entry *dents; + struct xfs_inode *dp = state->args->dp; + + args = state->args; + ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC); + ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC); + drop_leaf = drop_blk->bp->b_addr; + save_leaf = save_blk->bp->b_addr; + + dp->d_ops->leaf_hdr_from_disk(&savehdr, save_leaf); + dp->d_ops->leaf_hdr_from_disk(&drophdr, drop_leaf); + sents = dp->d_ops->leaf_ents_p(save_leaf); + dents = dp->d_ops->leaf_ents_p(drop_leaf); + + /* + * If there are any stale leaf entries, take this opportunity + * to purge them. + */ + if (drophdr.stale) + xfs_dir3_leaf_compact(args, &drophdr, drop_blk->bp); + if (savehdr.stale) + xfs_dir3_leaf_compact(args, &savehdr, save_blk->bp); + + /* + * Move the entries from drop to the appropriate end of save. + */ + drop_blk->hashval = be32_to_cpu(dents[drophdr.count - 1].hashval); + if (xfs_dir2_leafn_order(dp, save_blk->bp, drop_blk->bp)) + xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0, + save_blk->bp, &savehdr, sents, 0, + drophdr.count); + else + xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0, + save_blk->bp, &savehdr, sents, + savehdr.count, drophdr.count); + save_blk->hashval = be32_to_cpu(sents[savehdr.count - 1].hashval); + + /* log the changes made when moving the entries */ + dp->d_ops->leaf_hdr_to_disk(save_leaf, &savehdr); + dp->d_ops->leaf_hdr_to_disk(drop_leaf, &drophdr); + xfs_dir3_leaf_log_header(args, save_blk->bp); + xfs_dir3_leaf_log_header(args, drop_blk->bp); + + xfs_dir3_leaf_check(dp, save_blk->bp); + xfs_dir3_leaf_check(dp, drop_blk->bp); +} + +/* + * Top-level node form directory addname routine. + */ +int /* error */ +xfs_dir2_node_addname( + xfs_da_args_t *args) /* operation arguments */ +{ + xfs_da_state_blk_t *blk; /* leaf block for insert */ + int error; /* error return value */ + int rval; /* sub-return value */ + xfs_da_state_t *state; /* btree cursor */ + + trace_xfs_dir2_node_addname(args); + + /* + * Allocate and initialize the state (btree cursor). + */ + state = xfs_da_state_alloc(); + state->args = args; + state->mp = args->dp->i_mount; + /* + * Look up the name. We're not supposed to find it, but + * this gives us the insertion point. + */ + error = xfs_da3_node_lookup_int(state, &rval); + if (error) + rval = error; + if (rval != ENOENT) { + goto done; + } + /* + * Add the data entry to a data block. + * Extravalid is set to a freeblock found by lookup. + */ + rval = xfs_dir2_node_addname_int(args, + state->extravalid ? &state->extrablk : NULL); + if (rval) { + goto done; + } + blk = &state->path.blk[state->path.active - 1]; + ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC); + /* + * Add the new leaf entry. + */ + rval = xfs_dir2_leafn_add(blk->bp, args, blk->index); + if (rval == 0) { + /* + * It worked, fix the hash values up the btree. + */ + if (!(args->op_flags & XFS_DA_OP_JUSTCHECK)) + xfs_da3_fixhashpath(state, &state->path); + } else { + /* + * It didn't work, we need to split the leaf block. + */ + if (args->total == 0) { + ASSERT(rval == ENOSPC); + goto done; + } + /* + * Split the leaf block and insert the new entry. + */ + rval = xfs_da3_split(state); + } +done: + xfs_da_state_free(state); + return rval; +} + +/* + * Add the data entry for a node-format directory name addition. + * The leaf entry is added in xfs_dir2_leafn_add. + * We may enter with a freespace block that the lookup found. + */ +static int /* error */ +xfs_dir2_node_addname_int( + xfs_da_args_t *args, /* operation arguments */ + xfs_da_state_blk_t *fblk) /* optional freespace block */ +{ + xfs_dir2_data_hdr_t *hdr; /* data block header */ + xfs_dir2_db_t dbno; /* data block number */ + struct xfs_buf *dbp; /* data block buffer */ + xfs_dir2_data_entry_t *dep; /* data entry pointer */ + xfs_inode_t *dp; /* incore directory inode */ + xfs_dir2_data_unused_t *dup; /* data unused entry pointer */ + int error; /* error return value */ + xfs_dir2_db_t fbno; /* freespace block number */ + struct xfs_buf *fbp; /* freespace buffer */ + int findex; /* freespace entry index */ + xfs_dir2_free_t *free=NULL; /* freespace block structure */ + xfs_dir2_db_t ifbno; /* initial freespace block no */ + xfs_dir2_db_t lastfbno=0; /* highest freespace block no */ + int length; /* length of the new entry */ + int logfree; /* need to log free entry */ + xfs_mount_t *mp; /* filesystem mount point */ + int needlog; /* need to log data header */ + int needscan; /* need to rescan data frees */ + __be16 *tagp; /* data entry tag pointer */ + xfs_trans_t *tp; /* transaction pointer */ + __be16 *bests; + struct xfs_dir3_icfree_hdr freehdr; + struct xfs_dir2_data_free *bf; + + dp = args->dp; + mp = dp->i_mount; + tp = args->trans; + length = dp->d_ops->data_entsize(args->namelen); + /* + * If we came in with a freespace block that means that lookup + * found an entry with our hash value. This is the freespace + * block for that data entry. + */ + if (fblk) { + fbp = fblk->bp; + /* + * Remember initial freespace block number. + */ + ifbno = fblk->blkno; + free = fbp->b_addr; + findex = fblk->index; + bests = dp->d_ops->free_bests_p(free); + dp->d_ops->free_hdr_from_disk(&freehdr, free); + + /* + * This means the free entry showed that the data block had + * space for our entry, so we remembered it. + * Use that data block. + */ + if (findex >= 0) { + ASSERT(findex < freehdr.nvalid); + ASSERT(be16_to_cpu(bests[findex]) != NULLDATAOFF); + ASSERT(be16_to_cpu(bests[findex]) >= length); + dbno = freehdr.firstdb + findex; + } else { + /* + * The data block looked at didn't have enough room. + * We'll start at the beginning of the freespace entries. + */ + dbno = -1; + findex = 0; + } + } else { + /* + * Didn't come in with a freespace block, so no data block. + */ + ifbno = dbno = -1; + fbp = NULL; + findex = 0; + } + + /* + * If we don't have a data block yet, we're going to scan the + * freespace blocks looking for one. Figure out what the + * highest freespace block number is. + */ + if (dbno == -1) { + xfs_fileoff_t fo; /* freespace block number */ + + if ((error = xfs_bmap_last_offset(dp, &fo, XFS_DATA_FORK))) + return error; + lastfbno = xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)fo); + fbno = ifbno; + } + /* + * While we haven't identified a data block, search the freeblock + * data for a good data block. If we find a null freeblock entry, + * indicating a hole in the data blocks, remember that. + */ + while (dbno == -1) { + /* + * If we don't have a freeblock in hand, get the next one. + */ + if (fbp == NULL) { + /* + * Happens the first time through unless lookup gave + * us a freespace block to start with. + */ + if (++fbno == 0) + fbno = xfs_dir2_byte_to_db(args->geo, + XFS_DIR2_FREE_OFFSET); + /* + * If it's ifbno we already looked at it. + */ + if (fbno == ifbno) + fbno++; + /* + * If it's off the end we're done. + */ + if (fbno >= lastfbno) + break; + /* + * Read the block. There can be holes in the + * freespace blocks, so this might not succeed. + * This should be really rare, so there's no reason + * to avoid it. + */ + error = xfs_dir2_free_try_read(tp, dp, + xfs_dir2_db_to_da(args->geo, fbno), + &fbp); + if (error) + return error; + if (!fbp) + continue; + free = fbp->b_addr; + findex = 0; + } + /* + * Look at the current free entry. Is it good enough? + * + * The bests initialisation should be where the bufer is read in + * the above branch. But gcc is too stupid to realise that bests + * and the freehdr are actually initialised if they are placed + * there, so we have to do it here to avoid warnings. Blech. + */ + bests = dp->d_ops->free_bests_p(free); + dp->d_ops->free_hdr_from_disk(&freehdr, free); + if (be16_to_cpu(bests[findex]) != NULLDATAOFF && + be16_to_cpu(bests[findex]) >= length) + dbno = freehdr.firstdb + findex; + else { + /* + * Are we done with the freeblock? + */ + if (++findex == freehdr.nvalid) { + /* + * Drop the block. + */ + xfs_trans_brelse(tp, fbp); + fbp = NULL; + if (fblk && fblk->bp) + fblk->bp = NULL; + } + } + } + /* + * If we don't have a data block, we need to allocate one and make + * the freespace entries refer to it. + */ + if (unlikely(dbno == -1)) { + /* + * Not allowed to allocate, return failure. + */ + if ((args->op_flags & XFS_DA_OP_JUSTCHECK) || args->total == 0) + return ENOSPC; + + /* + * Allocate and initialize the new data block. + */ + if (unlikely((error = xfs_dir2_grow_inode(args, + XFS_DIR2_DATA_SPACE, + &dbno)) || + (error = xfs_dir3_data_init(args, dbno, &dbp)))) + return error; + + /* + * If (somehow) we have a freespace block, get rid of it. + */ + if (fbp) + xfs_trans_brelse(tp, fbp); + if (fblk && fblk->bp) + fblk->bp = NULL; + + /* + * Get the freespace block corresponding to the data block + * that was just allocated. + */ + fbno = dp->d_ops->db_to_fdb(args->geo, dbno); + error = xfs_dir2_free_try_read(tp, dp, + xfs_dir2_db_to_da(args->geo, fbno), + &fbp); + if (error) + return error; + + /* + * If there wasn't a freespace block, the read will + * return a NULL fbp. Allocate and initialize a new one. + */ + if (!fbp) { + error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, + &fbno); + if (error) + return error; + + if (dp->d_ops->db_to_fdb(args->geo, dbno) != fbno) { + xfs_alert(mp, + "%s: dir ino %llu needed freesp block %lld for\n" + " data block %lld, got %lld ifbno %llu lastfbno %d", + __func__, (unsigned long long)dp->i_ino, + (long long)dp->d_ops->db_to_fdb( + args->geo, dbno), + (long long)dbno, (long long)fbno, + (unsigned long long)ifbno, lastfbno); + if (fblk) { + xfs_alert(mp, + " fblk 0x%p blkno %llu index %d magic 0x%x", + fblk, + (unsigned long long)fblk->blkno, + fblk->index, + fblk->magic); + } else { + xfs_alert(mp, " ... fblk is NULL"); + } + XFS_ERROR_REPORT("xfs_dir2_node_addname_int", + XFS_ERRLEVEL_LOW, mp); + return EFSCORRUPTED; + } + + /* + * Get a buffer for the new block. + */ + error = xfs_dir3_free_get_buf(args, fbno, &fbp); + if (error) + return error; + free = fbp->b_addr; + bests = dp->d_ops->free_bests_p(free); + dp->d_ops->free_hdr_from_disk(&freehdr, free); + + /* + * Remember the first slot as our empty slot. + */ + freehdr.firstdb = + (fbno - xfs_dir2_byte_to_db(args->geo, + XFS_DIR2_FREE_OFFSET)) * + dp->d_ops->free_max_bests(args->geo); + } else { + free = fbp->b_addr; + bests = dp->d_ops->free_bests_p(free); + dp->d_ops->free_hdr_from_disk(&freehdr, free); + } + + /* + * Set the freespace block index from the data block number. + */ + findex = dp->d_ops->db_to_fdindex(args->geo, dbno); + /* + * If it's after the end of the current entries in the + * freespace block, extend that table. + */ + if (findex >= freehdr.nvalid) { + ASSERT(findex < dp->d_ops->free_max_bests(args->geo)); + freehdr.nvalid = findex + 1; + /* + * Tag new entry so nused will go up. + */ + bests[findex] = cpu_to_be16(NULLDATAOFF); + } + /* + * If this entry was for an empty data block + * (this should always be true) then update the header. + */ + if (bests[findex] == cpu_to_be16(NULLDATAOFF)) { + freehdr.nused++; + dp->d_ops->free_hdr_to_disk(fbp->b_addr, &freehdr); + xfs_dir2_free_log_header(args, fbp); + } + /* + * Update the real value in the table. + * We haven't allocated the data entry yet so this will + * change again. + */ + hdr = dbp->b_addr; + bf = dp->d_ops->data_bestfree_p(hdr); + bests[findex] = bf[0].length; + logfree = 1; + } + /* + * We had a data block so we don't have to make a new one. + */ + else { + /* + * If just checking, we succeeded. + */ + if (args->op_flags & XFS_DA_OP_JUSTCHECK) + return 0; + + /* + * Read the data block in. + */ + error = xfs_dir3_data_read(tp, dp, + xfs_dir2_db_to_da(args->geo, dbno), + -1, &dbp); + if (error) + return error; + hdr = dbp->b_addr; + bf = dp->d_ops->data_bestfree_p(hdr); + logfree = 0; + } + ASSERT(be16_to_cpu(bf[0].length) >= length); + /* + * Point to the existing unused space. + */ + dup = (xfs_dir2_data_unused_t *) + ((char *)hdr + be16_to_cpu(bf[0].offset)); + needscan = needlog = 0; + /* + * Mark the first part of the unused space, inuse for us. + */ + xfs_dir2_data_use_free(args, dbp, dup, + (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length, + &needlog, &needscan); + /* + * Fill in the new entry and log it. + */ + dep = (xfs_dir2_data_entry_t *)dup; + dep->inumber = cpu_to_be64(args->inumber); + dep->namelen = args->namelen; + memcpy(dep->name, args->name, dep->namelen); + dp->d_ops->data_put_ftype(dep, args->filetype); + tagp = dp->d_ops->data_entry_tag_p(dep); + *tagp = cpu_to_be16((char *)dep - (char *)hdr); + xfs_dir2_data_log_entry(args, dbp, dep); + /* + * Rescan the block for bestfree if needed. + */ + if (needscan) + xfs_dir2_data_freescan(dp, hdr, &needlog); + /* + * Log the data block header if needed. + */ + if (needlog) + xfs_dir2_data_log_header(args, dbp); + /* + * If the freespace entry is now wrong, update it. + */ + bests = dp->d_ops->free_bests_p(free); /* gcc is so stupid */ + if (be16_to_cpu(bests[findex]) != be16_to_cpu(bf[0].length)) { + bests[findex] = bf[0].length; + logfree = 1; + } + /* + * Log the freespace entry if needed. + */ + if (logfree) + xfs_dir2_free_log_bests(args, fbp, findex, findex); + /* + * Return the data block and offset in args, then drop the data block. + */ + args->blkno = (xfs_dablk_t)dbno; + args->index = be16_to_cpu(*tagp); + return 0; +} + +/* + * Lookup an entry in a node-format directory. + * All the real work happens in xfs_da3_node_lookup_int. + * The only real output is the inode number of the entry. + */ +int /* error */ +xfs_dir2_node_lookup( + xfs_da_args_t *args) /* operation arguments */ +{ + int error; /* error return value */ + int i; /* btree level */ + int rval; /* operation return value */ + xfs_da_state_t *state; /* btree cursor */ + + trace_xfs_dir2_node_lookup(args); + + /* + * Allocate and initialize the btree cursor. + */ + state = xfs_da_state_alloc(); + state->args = args; + state->mp = args->dp->i_mount; + /* + * Fill in the path to the entry in the cursor. + */ + error = xfs_da3_node_lookup_int(state, &rval); + if (error) + rval = error; + else if (rval == ENOENT && args->cmpresult == XFS_CMP_CASE) { + /* If a CI match, dup the actual name and return EEXIST */ + xfs_dir2_data_entry_t *dep; + + dep = (xfs_dir2_data_entry_t *) + ((char *)state->extrablk.bp->b_addr + + state->extrablk.index); + rval = xfs_dir_cilookup_result(args, dep->name, dep->namelen); + } + /* + * Release the btree blocks and leaf block. + */ + for (i = 0; i < state->path.active; i++) { + xfs_trans_brelse(args->trans, state->path.blk[i].bp); + state->path.blk[i].bp = NULL; + } + /* + * Release the data block if we have it. + */ + if (state->extravalid && state->extrablk.bp) { + xfs_trans_brelse(args->trans, state->extrablk.bp); + state->extrablk.bp = NULL; + } + xfs_da_state_free(state); + return rval; +} + +/* + * Remove an entry from a node-format directory. + */ +int /* error */ +xfs_dir2_node_removename( + struct xfs_da_args *args) /* operation arguments */ +{ + struct xfs_da_state_blk *blk; /* leaf block */ + int error; /* error return value */ + int rval; /* operation return value */ + struct xfs_da_state *state; /* btree cursor */ + + trace_xfs_dir2_node_removename(args); + + /* + * Allocate and initialize the btree cursor. + */ + state = xfs_da_state_alloc(); + state->args = args; + state->mp = args->dp->i_mount; + + /* Look up the entry we're deleting, set up the cursor. */ + error = xfs_da3_node_lookup_int(state, &rval); + if (error) + goto out_free; + + /* Didn't find it, upper layer screwed up. */ + if (rval != EEXIST) { + error = rval; + goto out_free; + } + + blk = &state->path.blk[state->path.active - 1]; + ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC); + ASSERT(state->extravalid); + /* + * Remove the leaf and data entries. + * Extrablk refers to the data block. + */ + error = xfs_dir2_leafn_remove(args, blk->bp, blk->index, + &state->extrablk, &rval); + if (error) + goto out_free; + /* + * Fix the hash values up the btree. + */ + xfs_da3_fixhashpath(state, &state->path); + /* + * If we need to join leaf blocks, do it. + */ + if (rval && state->path.active > 1) + error = xfs_da3_join(state); + /* + * If no errors so far, try conversion to leaf format. + */ + if (!error) + error = xfs_dir2_node_to_leaf(state); +out_free: + xfs_da_state_free(state); + return error; +} + +/* + * Replace an entry's inode number in a node-format directory. + */ +int /* error */ +xfs_dir2_node_replace( + xfs_da_args_t *args) /* operation arguments */ +{ + xfs_da_state_blk_t *blk; /* leaf block */ + xfs_dir2_data_hdr_t *hdr; /* data block header */ + xfs_dir2_data_entry_t *dep; /* data entry changed */ + int error; /* error return value */ + int i; /* btree level */ + xfs_ino_t inum; /* new inode number */ + xfs_dir2_leaf_t *leaf; /* leaf structure */ + xfs_dir2_leaf_entry_t *lep; /* leaf entry being changed */ + int rval; /* internal return value */ + xfs_da_state_t *state; /* btree cursor */ + + trace_xfs_dir2_node_replace(args); + + /* + * Allocate and initialize the btree cursor. + */ + state = xfs_da_state_alloc(); + state->args = args; + state->mp = args->dp->i_mount; + inum = args->inumber; + /* + * Lookup the entry to change in the btree. + */ + error = xfs_da3_node_lookup_int(state, &rval); + if (error) { + rval = error; + } + /* + * It should be found, since the vnodeops layer has looked it up + * and locked it. But paranoia is good. + */ + if (rval == EEXIST) { + struct xfs_dir2_leaf_entry *ents; + /* + * Find the leaf entry. + */ + blk = &state->path.blk[state->path.active - 1]; + ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC); + leaf = blk->bp->b_addr; + ents = args->dp->d_ops->leaf_ents_p(leaf); + lep = &ents[blk->index]; + ASSERT(state->extravalid); + /* + * Point to the data entry. + */ + hdr = state->extrablk.bp->b_addr; + ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC)); + dep = (xfs_dir2_data_entry_t *) + ((char *)hdr + + xfs_dir2_dataptr_to_off(args->geo, + be32_to_cpu(lep->address))); + ASSERT(inum != be64_to_cpu(dep->inumber)); + /* + * Fill in the new inode number and log the entry. + */ + dep->inumber = cpu_to_be64(inum); + args->dp->d_ops->data_put_ftype(dep, args->filetype); + xfs_dir2_data_log_entry(args, state->extrablk.bp, dep); + rval = 0; + } + /* + * Didn't find it, and we're holding a data block. Drop it. + */ + else if (state->extravalid) { + xfs_trans_brelse(args->trans, state->extrablk.bp); + state->extrablk.bp = NULL; + } + /* + * Release all the buffers in the cursor. + */ + for (i = 0; i < state->path.active; i++) { + xfs_trans_brelse(args->trans, state->path.blk[i].bp); + state->path.blk[i].bp = NULL; + } + xfs_da_state_free(state); + return rval; +} + +/* + * Trim off a trailing empty freespace block. + * Return (in rvalp) 1 if we did it, 0 if not. + */ +int /* error */ +xfs_dir2_node_trim_free( + xfs_da_args_t *args, /* operation arguments */ + xfs_fileoff_t fo, /* free block number */ + int *rvalp) /* out: did something */ +{ + struct xfs_buf *bp; /* freespace buffer */ + xfs_inode_t *dp; /* incore directory inode */ + int error; /* error return code */ + xfs_dir2_free_t *free; /* freespace structure */ + xfs_mount_t *mp; /* filesystem mount point */ + xfs_trans_t *tp; /* transaction pointer */ + struct xfs_dir3_icfree_hdr freehdr; + + dp = args->dp; + mp = dp->i_mount; + tp = args->trans; + /* + * Read the freespace block. + */ + error = xfs_dir2_free_try_read(tp, dp, fo, &bp); + if (error) + return error; + /* + * There can be holes in freespace. If fo is a hole, there's + * nothing to do. + */ + if (!bp) + return 0; + free = bp->b_addr; + dp->d_ops->free_hdr_from_disk(&freehdr, free); + + /* + * If there are used entries, there's nothing to do. + */ + if (freehdr.nused > 0) { + xfs_trans_brelse(tp, bp); + *rvalp = 0; + return 0; + } + /* + * Blow the block away. + */ + error = xfs_dir2_shrink_inode(args, + xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)fo), bp); + if (error) { + /* + * Can't fail with ENOSPC since that only happens with no + * space reservation, when breaking up an extent into two + * pieces. This is the last block of an extent. + */ + ASSERT(error != ENOSPC); + xfs_trans_brelse(tp, bp); + return error; + } + /* + * Return that we succeeded. + */ + *rvalp = 1; + return 0; +} |