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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
  * Copyright (c) 2013 Red Hat, Inc.
  * All Rights Reserved.
  */
 #include "xfs.h"
 #include "xfs_fs.h"
 #include "xfs_shared.h"
 #include "xfs_format.h"
 #include "xfs_log_format.h"
 #include "xfs_trans_resv.h"
 #include "xfs_mount.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_log.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);
 
 /*
  * Convert data space db to the corresponding free db.
  */
 static xfs_dir2_db_t
 xfs_dir2_db_to_fdb(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
 {
     return xfs_dir2_byte_to_db(geo, XFS_DIR2_FREE_OFFSET) +
             (db / geo->free_max_bests);
 }
 
 /*
  * Convert data space db to the corresponding index in a free db.
  */
 static int
 xfs_dir2_db_to_fdindex(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
 {
     return db % geo->free_max_bests;
 }
 
 /*
  * Check internal consistency of a leafn block.
  */
 #ifdef DEBUG
 static xfs_failaddr_t
 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;
 
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &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) != xfs_buf_daddr(bp))
             return __this_address;
     } else if (leafhdr.magic != XFS_DIR2_LEAFN_MAGIC)
         return __this_address;
 
     return xfs_dir3_leaf_check_int(dp->i_mount, &leafhdr, leaf, false);
 }
 
 static inline void
 xfs_dir3_leaf_check(
     struct xfs_inode    *dp,
     struct xfs_buf      *bp)
 {
     xfs_failaddr_t      fa;
 
     fa = xfs_dir3_leafn_check(dp, bp);
     if (!fa)
         return;
     xfs_corruption_error(__func__, XFS_ERRLEVEL_LOW, dp->i_mount,
             bp->b_addr, BBTOB(bp->b_length), __FILE__, __LINE__,
             fa);
     ASSERT(0);
 }
 #else
 #define xfs_dir3_leaf_check(dp, bp)
 #endif
 
 static xfs_failaddr_t
 xfs_dir3_free_verify(
     struct xfs_buf      *bp)
 {
     struct xfs_mount    *mp = bp->b_mount;
     struct xfs_dir2_free_hdr *hdr = bp->b_addr;
 
     if (!xfs_verify_magic(bp, hdr->magic))
         return __this_address;
 
     if (xfs_has_crc(mp)) {
         struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
 
         if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_meta_uuid))
             return __this_address;
         if (be64_to_cpu(hdr3->blkno) != xfs_buf_daddr(bp))
             return __this_address;
         if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->lsn)))
             return __this_address;
     }
 
     /* XXX: should bounds check the xfs_dir3_icfree_hdr here */
 
     return NULL;
 }
 
 static void
 xfs_dir3_free_read_verify(
     struct xfs_buf  *bp)
 {
     struct xfs_mount    *mp = bp->b_mount;
     xfs_failaddr_t      fa;
 
     if (xfs_has_crc(mp) &&
         !xfs_buf_verify_cksum(bp, XFS_DIR3_FREE_CRC_OFF))
         xfs_verifier_error(bp, -EFSBADCRC, __this_address);
     else {
         fa = xfs_dir3_free_verify(bp);
         if (fa)
             xfs_verifier_error(bp, -EFSCORRUPTED, fa);
     }
 }
 
 static void
 xfs_dir3_free_write_verify(
     struct xfs_buf  *bp)
 {
     struct xfs_mount    *mp = bp->b_mount;
     struct xfs_buf_log_item *bip = bp->b_log_item;
     struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
     xfs_failaddr_t      fa;
 
     fa = xfs_dir3_free_verify(bp);
     if (fa) {
         xfs_verifier_error(bp, -EFSCORRUPTED, fa);
         return;
     }
 
     if (!xfs_has_crc(mp))
         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 = {
     .name = "xfs_dir3_free",
     .magic = { cpu_to_be32(XFS_DIR2_FREE_MAGIC),
            cpu_to_be32(XFS_DIR3_FREE_MAGIC) },
     .verify_read = xfs_dir3_free_read_verify,
     .verify_write = xfs_dir3_free_write_verify,
     .verify_struct = xfs_dir3_free_verify,
 };
 
 /* Everything ok in the free block header? */
 static xfs_failaddr_t
 xfs_dir3_free_header_check(
     struct xfs_inode    *dp,
     xfs_dablk_t     fbno,
     struct xfs_buf      *bp)
 {
     struct xfs_mount    *mp = dp->i_mount;
     int         maxbests = mp->m_dir_geo->free_max_bests;
     unsigned int        firstdb;
 
     firstdb = (xfs_dir2_da_to_db(mp->m_dir_geo, fbno) -
            xfs_dir2_byte_to_db(mp->m_dir_geo, XFS_DIR2_FREE_OFFSET)) *
             maxbests;
     if (xfs_has_crc(mp)) {
         struct xfs_dir3_free_hdr *hdr3 = bp->b_addr;
 
         if (be32_to_cpu(hdr3->firstdb) != firstdb)
             return __this_address;
         if (be32_to_cpu(hdr3->nvalid) > maxbests)
             return __this_address;
         if (be32_to_cpu(hdr3->nvalid) < be32_to_cpu(hdr3->nused))
             return __this_address;
         if (be64_to_cpu(hdr3->hdr.owner) != dp->i_ino)
             return __this_address;
     } else {
         struct xfs_dir2_free_hdr *hdr = bp->b_addr;
 
         if (be32_to_cpu(hdr->firstdb) != firstdb)
             return __this_address;
         if (be32_to_cpu(hdr->nvalid) > maxbests)
             return __this_address;
         if (be32_to_cpu(hdr->nvalid) < be32_to_cpu(hdr->nused))
             return __this_address;
     }
     return NULL;
 }
 
 static int
 __xfs_dir3_free_read(
     struct xfs_trans    *tp,
     struct xfs_inode    *dp,
     xfs_dablk_t     fbno,
     unsigned int        flags,
     struct xfs_buf      **bpp)
 {
     xfs_failaddr_t      fa;
     int         err;
 
     err = xfs_da_read_buf(tp, dp, fbno, flags, bpp, XFS_DATA_FORK,
             &xfs_dir3_free_buf_ops);
     if (err || !*bpp)
         return err;
 
     /* Check things that we can't do in the verifier. */
     fa = xfs_dir3_free_header_check(dp, fbno, *bpp);
     if (fa) {
         __xfs_buf_mark_corrupt(*bpp, fa);
         xfs_trans_brelse(tp, *bpp);
         *bpp = NULL;
         return -EFSCORRUPTED;
     }
 
     /* try read returns without an error or *bpp if it lands in a hole */
     if (tp)
         xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_FREE_BUF);
 
     return 0;
 }
 
 void
 xfs_dir2_free_hdr_from_disk(
     struct xfs_mount        *mp,
     struct xfs_dir3_icfree_hdr  *to,
     struct xfs_dir2_free        *from)
 {
     if (xfs_has_crc(mp)) {
         struct xfs_dir3_free    *from3 = (struct xfs_dir3_free *)from;
 
         to->magic = be32_to_cpu(from3->hdr.hdr.magic);
         to->firstdb = be32_to_cpu(from3->hdr.firstdb);
         to->nvalid = be32_to_cpu(from3->hdr.nvalid);
         to->nused = be32_to_cpu(from3->hdr.nused);
         to->bests = from3->bests;
 
         ASSERT(to->magic == XFS_DIR3_FREE_MAGIC);
     } else {
         to->magic = be32_to_cpu(from->hdr.magic);
         to->firstdb = be32_to_cpu(from->hdr.firstdb);
         to->nvalid = be32_to_cpu(from->hdr.nvalid);
         to->nused = be32_to_cpu(from->hdr.nused);
         to->bests = from->bests;
 
         ASSERT(to->magic == XFS_DIR2_FREE_MAGIC);
     }
 }
 
 static void
 xfs_dir2_free_hdr_to_disk(
     struct xfs_mount        *mp,
     struct xfs_dir2_free        *to,
     struct xfs_dir3_icfree_hdr  *from)
 {
     if (xfs_has_crc(mp)) {
         struct xfs_dir3_free    *to3 = (struct xfs_dir3_free *)to;
 
         ASSERT(from->magic == XFS_DIR3_FREE_MAGIC);
 
         to3->hdr.hdr.magic = cpu_to_be32(from->magic);
         to3->hdr.firstdb = cpu_to_be32(from->firstdb);
         to3->hdr.nvalid = cpu_to_be32(from->nvalid);
         to3->hdr.nused = cpu_to_be32(from->nused);
     } else {
         ASSERT(from->magic == XFS_DIR2_FREE_MAGIC);
 
         to->hdr.magic = cpu_to_be32(from->magic);
         to->hdr.firstdb = cpu_to_be32(from->firstdb);
         to->hdr.nvalid = cpu_to_be32(from->nvalid);
         to->hdr.nused = cpu_to_be32(from->nused);
     }
 }
 
 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, 0, 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, XFS_DABUF_MAP_HOLE_OK, 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),
             &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_has_crc(mp)) {
         struct xfs_dir3_free_hdr *hdr3 = bp->b_addr;
 
         hdr.magic = XFS_DIR3_FREE_MAGIC;
 
         hdr3->hdr.blkno = cpu_to_be64(xfs_buf_daddr(bp));
         hdr3->hdr.owner = cpu_to_be64(dp->i_ino);
         uuid_copy(&hdr3->hdr.uuid, &mp->m_sb.sb_meta_uuid);
     } else
         hdr.magic = XFS_DIR2_FREE_MAGIC;
     xfs_dir2_free_hdr_to_disk(mp, 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_dir3_icfree_hdr *hdr,
     struct xfs_buf      *bp,
     int         first,      /* first entry to log */
     int         last)       /* last entry to log */
 {
     struct xfs_dir2_free    *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));
     xfs_trans_log_buf(args->trans, bp,
               (char *)&hdr->bests[first] - (char *)free,
               (char *)&hdr->bests[last] - (char *)free +
                sizeof(hdr->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->geo->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 */
     __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 */
     int         n;      /* count of live freespc ents */
     xfs_dir2_data_off_t off;        /* freespace entry value */
     xfs_trans_t     *tp;        /* transaction pointer */
     struct xfs_dir3_icfree_hdr freehdr;
 
     trace_xfs_dir2_leaf_to_node(args);
 
     dp = args->dp;
     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;
 
     xfs_dir2_free_hdr_from_disk(dp->i_mount, &freehdr, fbp->b_addr);
     leaf = lbp->b_addr;
     ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
     if (be32_to_cpu(ltp->bestcount) >
                 (uint)dp->i_disk_size / args->geo->blksize) {
         xfs_buf_mark_corrupt(lbp);
         return -EFSCORRUPTED;
     }
 
     /*
      * Copy freespace entries from the leaf block to the new block.
      * Count active entries.
      */
     from = xfs_dir2_leaf_bests_p(ltp);
     for (i = n = 0; i < be32_to_cpu(ltp->bestcount); i++, from++) {
         off = be16_to_cpu(*from);
         if (off != NULLDATAOFF)
             n++;
         freehdr.bests[i] = cpu_to_be16(off);
     }
 
     /*
      * Now initialize the freespace block header.
      */
     freehdr.nused = n;
     freehdr.nvalid = be32_to_cpu(ltp->bestcount);
 
     xfs_dir2_free_hdr_to_disk(dp->i_mount, fbp->b_addr, &freehdr);
     xfs_dir2_free_log_bests(args, &freehdr, 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 */
     struct xfs_da_args  *args,      /* operation arguments */
     int         index)      /* insertion pt for new entry */
 {
     struct xfs_dir3_icleaf_hdr leafhdr;
     struct xfs_inode    *dp = args->dp;
     struct xfs_dir2_leaf    *leaf = bp->b_addr;
     struct xfs_dir2_leaf_entry *lep;
     struct xfs_dir2_leaf_entry *ents;
     int         compact;    /* compacting stale leaves */
     int         highstale = 0;  /* next stale entry */
     int         lfloghigh;  /* high leaf entry logging */
     int         lfloglow;   /* low leaf entry logging */
     int         lowstale = 0;   /* previous stale entry */
 
     trace_xfs_dir2_leafn_add(args, index);
 
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, leaf);
     ents = leafhdr.ents;
 
     /*
      * Quick check just to make sure we are not going to index
      * into other peoples memory
      */
     if (index < 0) {
         xfs_buf_mark_corrupt(bp);
         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 == args->geo->leaf_max_ents) {
         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));
 
     xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, &leafhdr);
     xfs_dir3_leaf_log_header(args, bp);
     xfs_dir3_leaf_log_ents(args, &leafhdr, 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;
 
     xfs_dir2_free_hdr_from_disk(dp->i_mount, &hdr, bp->b_addr);
 
     ASSERT((hdr.firstdb % dp->i_mount->m_dir_geo->free_max_bests) == 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_leaf_lasthash(
     struct xfs_inode *dp,
     struct xfs_buf  *bp,            /* leaf buffer */
     int     *count)         /* count of entries in leaf */
 {
     struct xfs_dir3_icleaf_hdr leafhdr;
 
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, bp->b_addr);
 
     ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
            leafhdr.magic == XFS_DIR3_LEAFN_MAGIC ||
            leafhdr.magic == XFS_DIR2_LEAF1_MAGIC ||
            leafhdr.magic == XFS_DIR3_LEAF1_MAGIC);
 
     if (count)
         *count = leafhdr.count;
     if (!leafhdr.count)
         return 0;
     return be32_to_cpu(leafhdr.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_dir3_icleaf_hdr leafhdr;
 
     dp = args->dp;
     tp = args->trans;
     mp = dp->i_mount;
     leaf = bp->b_addr;
     xfs_dir2_leaf_hdr_from_disk(mp, &leafhdr, 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 = xfs_dir2_data_entsize(mp, args->namelen);
     /*
      * Loop over leaf entries with the right hash value.
      */
     for (lep = &leafhdr.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) {
             struct xfs_dir3_icfree_hdr freehdr;
 
             curdb = newdb;
             /*
              * Convert the data block to the free block
              * holding its freespace information.
              */
             newfdb = xfs_dir2_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 = xfs_dir2_db_to_fdindex(args->geo, curdb);
             /*
              * If it has room, return it.
              */
             xfs_dir2_free_hdr_from_disk(mp, &freehdr, free);
             if (XFS_IS_CORRUPT(mp,
                        freehdr.bests[fi] ==
                        cpu_to_be16(NULLDATAOFF))) {
                 if (curfdb != newfdb)
                     xfs_trans_brelse(tp, curbp);
                 return -EFSCORRUPTED;
             }
             curfdb = newfdb;
             if (be16_to_cpu(freehdr.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_dir3_icleaf_hdr leafhdr;
 
     dp = args->dp;
     tp = args->trans;
     mp = dp->i_mount;
     leaf = bp->b_addr;
     xfs_dir2_leaf_hdr_from_disk(mp, &leafhdr, leaf);
 
     xfs_dir3_leaf_check(dp, bp);
     if (leafhdr.count <= 0) {
         xfs_buf_mark_corrupt(bp);
         return -EFSCORRUPTED;
     }
 
     /*
      * 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 = &leafhdr.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),
                         0, &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 = xfs_dir2_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 = xfs_dir2_data_get_ftype(mp, 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, dhdr, 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, dhdr, 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, shdr, 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;
 
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &hdr1, leaf1);
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &hdr2, leaf2);
     ents1 = hdr1.ents;
     ents2 = hdr2.ents;
 
     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_blocks;    /* 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.
      */
     swap_blocks = xfs_dir2_leafn_order(dp, blk1->bp, blk2->bp);
     if (swap_blocks)
         swap(blk1, blk2);
 
     leaf1 = blk1->bp->b_addr;
     leaf2 = blk2->bp->b_addr;
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &hdr1, leaf1);
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &hdr2, leaf2);
     ents1 = hdr1.ents;
     ents2 = hdr2.ents;
 
     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 */
     xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf1, &hdr1);
     xfs_dir2_leaf_hdr_to_disk(dp->i_mount, 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_blocks;
     else if (hdr1.count > hdr2.count)
         state->inleaf = !swap_blocks;
     else
         state->inleaf = swap_blocks ^ (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;
     struct xfs_dir3_icfree_hdr freehdr;
     struct xfs_inode    *dp = args->dp;
 
     xfs_dir2_free_hdr_from_disk(dp->i_mount, &freehdr, free);
     if (hdr) {
         /*
          * Data block is not empty, just set the free entry to the new
          * value.
          */
         freehdr.bests[findex] = cpu_to_be16(longest);
         xfs_dir2_free_log_bests(args, &freehdr, 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 (freehdr.bests[i] != cpu_to_be16(NULLDATAOFF))
                 break;
         }
         freehdr.nvalid = i + 1;
         logfree = 0;
     } else {
         /* Not the last entry, just punch it out.  */
         freehdr.bests[findex] = cpu_to_be16(NULLDATAOFF);
         logfree = 1;
     }
 
     xfs_dir2_free_hdr_to_disk(dp->i_mount, 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, &freehdr, 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 */
 {
     struct xfs_da_geometry  *geo = args->geo;
     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 */
     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;
 
     trace_xfs_dir2_leafn_remove(args, index);
 
     dp = args->dp;
     tp = args->trans;
     leaf = bp->b_addr;
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, leaf);
 
     /*
      * Point to the entry we're removing.
      */
     lep = &leafhdr.ents[index];
 
     /*
      * Extract the data block and offset from the entry.
      */
     db = xfs_dir2_dataptr_to_db(geo, be32_to_cpu(lep->address));
     ASSERT(dblk->blkno == db);
     off = xfs_dir2_dataptr_to_off(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++;
     xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, &leafhdr);
     xfs_dir3_leaf_log_header(args, bp);
 
     lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
     xfs_dir3_leaf_log_ents(args, &leafhdr, 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 = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
     longest = be16_to_cpu(bf[0].length);
     needlog = needscan = 0;
     xfs_dir2_data_make_free(args, dbp, off,
         xfs_dir2_data_entsize(dp->i_mount, 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->i_mount, 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 = xfs_dir2_db_to_fdb(geo, db);
         error = xfs_dir2_free_read(tp, dp, xfs_dir2_db_to_da(geo, fdb),
                        &fbp);
         if (error)
             return error;
         free = fbp->b_addr;
 #ifdef DEBUG
     {
         struct xfs_dir3_icfree_hdr freehdr;
 
         xfs_dir2_free_hdr_from_disk(dp->i_mount, &freehdr, free);
         ASSERT(freehdr.firstdb == geo->free_max_bests *
             (fdb - xfs_dir2_byte_to_db(geo, XFS_DIR2_FREE_OFFSET)));
     }
 #endif
         /*
          * Calculate which entry we need to fix.
          */
         findex = xfs_dir2_db_to_fdindex(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 == geo->blksize - geo->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 = (geo->leaf_hdr_size +
          (uint)sizeof(leafhdr.ents) * (leafhdr.count - leafhdr.stale)) <
         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 */
     struct xfs_inode    *dp;
 
     /*
      * Allocate space for a new leaf node.
      */
     args = state->args;
     dp = args->dp;
     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_leaf_lasthash(dp, oldblk->bp, NULL);
     newblk->hashval = xfs_dir2_leaf_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;
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, leaf);
     ents = leafhdr.ents;
     xfs_dir3_leaf_check(dp, blk->bp);
 
     count = leafhdr.count - leafhdr.stale;
     bytes = state->args->geo->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, &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;
         xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &hdr2, leaf);
         ents = hdr2.ents;
         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;
 
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &savehdr, save_leaf);
     xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &drophdr, drop_leaf);
     sents = savehdr.ents;
     dents = drophdr.ents;
 
     /*
      * 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 */
     xfs_dir2_leaf_hdr_to_disk(dp->i_mount, save_leaf, &savehdr);
     xfs_dir2_leaf_hdr_to_disk(dp->i_mount, 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);
 }
 
 /*
  * Add a new data block to the directory at the free space index that the caller
  * has specified.
  */
 static int
 xfs_dir2_node_add_datablk(
     struct xfs_da_args  *args,
     struct xfs_da_state_blk *fblk,
     xfs_dir2_db_t       *dbno,
     struct xfs_buf      **dbpp,
     struct xfs_buf      **fbpp,
     struct xfs_dir3_icfree_hdr *hdr,
     int         *findex)
 {
     struct xfs_inode    *dp = args->dp;
     struct xfs_trans    *tp = args->trans;
     struct xfs_mount    *mp = dp->i_mount;
     struct xfs_dir2_data_free *bf;
     xfs_dir2_db_t       fbno;
     struct xfs_buf      *fbp;
     struct xfs_buf      *dbp;
     int         error;
 
     /* Not allowed to allocate, return failure. */
     if (args->total == 0)
         return -ENOSPC;
 
     /* Allocate and initialize the new data block.  */
     error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE, dbno);
     if (error)
         return error;
     error = xfs_dir3_data_init(args, *dbno, &dbp);
     if (error)
         return error;
 
     /*
      * Get the freespace block corresponding to the data block
      * that was just allocated.
      */
     fbno = xfs_dir2_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 (XFS_IS_CORRUPT(mp,
                    xfs_dir2_db_to_fdb(args->geo, *dbno) !=
                    fbno)) {
             xfs_alert(mp,
 "%s: dir ino %llu needed freesp block %lld for data block %lld, got %lld",
                 __func__, (unsigned long long)dp->i_ino,
                 (long long)xfs_dir2_db_to_fdb(args->geo, *dbno),
                 (long long)*dbno, (long long)fbno);
             if (fblk) {
                 xfs_alert(mp,
             " fblk "PTR_FMT" blkno %llu index %d magic 0x%x",
                     fblk, (unsigned long long)fblk->blkno,
                     fblk->index, fblk->magic);
             } else {
                 xfs_alert(mp, " ... fblk is NULL");
             }
             return -EFSCORRUPTED;
         }
 
         /* Get a buffer for the new block. */
         error = xfs_dir3_free_get_buf(args, fbno, &fbp);
         if (error)
             return error;
         xfs_dir2_free_hdr_from_disk(mp, hdr, fbp->b_addr);
 
         /* Remember the first slot as our empty slot. */
         hdr->firstdb = (fbno - xfs_dir2_byte_to_db(args->geo,
                             XFS_DIR2_FREE_OFFSET)) *
                 args->geo->free_max_bests;
     } else {
         xfs_dir2_free_hdr_from_disk(mp, hdr, fbp->b_addr);
     }
 
     /* Set the freespace block index from the data block number. */
     *findex = xfs_dir2_db_to_fdindex(args->geo, *dbno);
 
     /* Extend the freespace table if the new data block is off the end. */
     if (*findex >= hdr->nvalid) {
         ASSERT(*findex < args->geo->free_max_bests);
         hdr->nvalid = *findex + 1;
         hdr->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 (hdr->bests[*findex] == cpu_to_be16(NULLDATAOFF)) {
         hdr->nused++;
         xfs_dir2_free_hdr_to_disk(mp, fbp->b_addr, hdr);
         xfs_dir2_free_log_header(args, fbp);
     }
 
     /* Update the freespace value for the new block in the table. */
     bf = xfs_dir2_data_bestfree_p(mp, dbp->b_addr);
     hdr->bests[*findex] = bf[0].length;
 
     *dbpp = dbp;
     *fbpp = fbp;
     return 0;
 }
 
 static int
 xfs_dir2_node_find_freeblk(
     struct xfs_da_args  *args,
     struct xfs_da_state_blk *fblk,
     xfs_dir2_db_t       *dbnop,
     struct xfs_buf      **fbpp,
     struct xfs_dir3_icfree_hdr *hdr,
     int         *findexp,
     int         length)
 {
     struct xfs_inode    *dp = args->dp;
     struct xfs_trans    *tp = args->trans;
     struct xfs_buf      *fbp = NULL;
     xfs_dir2_db_t       firstfbno;
     xfs_dir2_db_t       lastfbno;
     xfs_dir2_db_t       ifbno = -1;
     xfs_dir2_db_t       dbno = -1;
     xfs_dir2_db_t       fbno;
     xfs_fileoff_t       fo;
     int         findex = 0;
     int         error;
 
     /*
      * 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;
         findex = fblk->index;
         xfs_dir2_free_hdr_from_disk(dp->i_mount, hdr, fbp->b_addr);
         if (findex >= 0) {
             /* caller already found the freespace for us. */
             ASSERT(findex < hdr->nvalid);
             ASSERT(be16_to_cpu(hdr->bests[findex]) != NULLDATAOFF);
             ASSERT(be16_to_cpu(hdr->bests[findex]) >= length);
             dbno = hdr->firstdb + findex;
             goto found_block;
         }
 
         /*
          * The data block looked at didn't have enough room.
          * We'll start at the beginning of the freespace entries.
          */
         ifbno = fblk->blkno;
         xfs_trans_brelse(tp, fbp);
         fbp = NULL;
         fblk->bp = NULL;
     }
 
     /*
      * If we don't have a data block yet, we're going to scan the freespace
      * data for a data block with enough free space in it.
      */
     error = xfs_bmap_last_offset(dp, &fo, XFS_DATA_FORK);
     if (error)
         return error;
     lastfbno = xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)fo);
     firstfbno = xfs_dir2_byte_to_db(args->geo, XFS_DIR2_FREE_OFFSET);
 
     for (fbno = lastfbno - 1; fbno >= firstfbno; fbno--) {
         /* If it's ifbno we already looked at it. */
         if (fbno == ifbno)
             continue;
 
         /*
          * 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;
 
         xfs_dir2_free_hdr_from_disk(dp->i_mount, hdr, fbp->b_addr);
 
         /* Scan the free entry array for a large enough free space. */
         for (findex = hdr->nvalid - 1; findex >= 0; findex--) {
             if (be16_to_cpu(hdr->bests[findex]) != NULLDATAOFF &&
                 be16_to_cpu(hdr->bests[findex]) >= length) {
                 dbno = hdr->firstdb + findex;
                 goto found_block;
             }
         }
 
         /* Didn't find free space, go on to next free block */
         xfs_trans_brelse(tp, fbp);
     }
 
 found_block:
     *dbnop = dbno;
     *fbpp = fbp;
     *findexp = findex;
     return 0;
 }
 
 /*
  * 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
 xfs_dir2_node_addname_int(
     struct xfs_da_args  *args,      /* operation arguments */
     struct xfs_da_state_blk *fblk)      /* optional freespace block */
 {
     struct xfs_dir2_data_unused *dup;   /* data unused entry pointer */
     struct xfs_dir2_data_entry *dep;    /* data entry pointer */
     struct xfs_dir2_data_hdr *hdr;      /* data block header */
     struct xfs_dir2_data_free *bf;
     struct xfs_trans    *tp = args->trans;
     struct xfs_inode    *dp = args->dp;
     struct xfs_dir3_icfree_hdr freehdr;
     struct xfs_buf      *dbp;       /* data block buffer */
     struct xfs_buf      *fbp;       /* freespace buffer */
     xfs_dir2_data_aoff_t    aoff;
     xfs_dir2_db_t       dbno;       /* data block number */
     int         error;      /* error return value */
     int         findex;     /* freespace entry index */
     int         length;     /* length of the new entry */
     int         logfree = 0;    /* need to log free entry */
     int         needlog = 0;    /* need to log data header */
     int         needscan = 0;   /* need to rescan data frees */
     __be16          *tagp;      /* data entry tag pointer */
 
     length = xfs_dir2_data_entsize(dp->i_mount, args->namelen);
     error = xfs_dir2_node_find_freeblk(args, fblk, &dbno, &fbp, &freehdr,
                        &findex, length);
     if (error)
         return error;
 
     /*
      * Now we know if we must allocate blocks, so if we are checking whether
      * we can insert without allocation then we can return now.
      */
     if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
         if (dbno == -1)
             return -ENOSPC;
         return 0;
     }
 
     /*
      * If we don't have a data block, we need to allocate one and make
      * the freespace entries refer to it.
      */
     if (dbno == -1) {
         /* we're going to have to log the free block index later */
         logfree = 1;
         error = xfs_dir2_node_add_datablk(args, fblk, &dbno, &dbp, &fbp,
                           &freehdr, &findex);
     } else {
         /* Read the data block in. */
         error = xfs_dir3_data_read(tp, dp,
                        xfs_dir2_db_to_da(args->geo, dbno),
                        0, &dbp);
     }
     if (error)
         return error;
 
     /* setup for data block up now */
     hdr = dbp->b_addr;
     bf = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
     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));
 
     /* Mark the first part of the unused space, inuse for us. */
     aoff = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr);
     error = xfs_dir2_data_use_free(args, dbp, dup, aoff, length,
             &needlog, &needscan);
     if (error) {
         xfs_trans_brelse(tp, dbp);
         return error;
     }
 
     /* 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);
     xfs_dir2_data_put_ftype(dp->i_mount, dep, args->filetype);
     tagp = xfs_dir2_data_entry_tag_p(dp->i_mount, dep);
     *tagp = cpu_to_be16((char *)dep - (char *)hdr);
     xfs_dir2_data_log_entry(args, dbp, dep);
 
     /* Rescan the freespace and log the data block if needed. */
     if (needscan)
         xfs_dir2_data_freescan(dp->i_mount, hdr, &needlog);
     if (needlog)
         xfs_dir2_data_log_header(args, dbp);
 
     /* If the freespace block entry is now wrong, update it. */
     if (freehdr.bests[findex] != bf[0].length) {
         freehdr.bests[findex] = bf[0].length;
         logfree = 1;
     }
 
     /* Log the freespace entry if needed. */
     if (logfree)
         xfs_dir2_free_log_bests(args, &freehdr, fbp, findex, findex);
 
     /* Return the data block and offset in args. */
     args->blkno = (xfs_dablk_t)dbno;
     args->index = be16_to_cpu(*tagp);
     return 0;
 }
 
 /*
  * 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(args);
     /*
      * 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;
 }
 
 /*
  * 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(args);
 
     /*
      * 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(args);
 
     /* 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 */
     int         ftype;      /* new file type */
     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(args);
 
     /*
      * We have to save new inode number and ftype since
      * xfs_da3_node_lookup_int() is going to overwrite them
      */
     inum = args->inumber;
     ftype = args->filetype;
 
     /*
      * 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_dir3_icleaf_hdr  leafhdr;
 
         /*
          * Find the leaf entry.
          */
         blk = &state->path.blk[state->path.active - 1];
         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
         ASSERT(state->extravalid);
 
         xfs_dir2_leaf_hdr_from_disk(state->mp, &leafhdr,
                         blk->bp->b_addr);
         /*
          * 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(leafhdr.ents[blk->index].address)));
         ASSERT(inum != be64_to_cpu(dep->inumber));
         /*
          * Fill in the new inode number and log the entry.
          */
         dep->inumber = cpu_to_be64(inum);
         xfs_dir2_data_put_ftype(state->mp, dep, ftype);
         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_trans_t     *tp;        /* transaction pointer */
     struct xfs_dir3_icfree_hdr freehdr;
 
     dp = args->dp;
     tp = args->trans;
 
     *rvalp = 0;
 
     /*
      * 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;
     xfs_dir2_free_hdr_from_disk(dp->i_mount, &freehdr, free);
 
     /*
      * If there are used entries, there's nothing to do.
      */
     if (freehdr.nused > 0) {
         xfs_trans_brelse(tp, bp);
         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;
 }

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