fs/xfs/xfs_dir2_block.h

   1 /*
   2  * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #ifndef __XFS_DIR2_BLOCK_H__
  19 #define __XFS_DIR2_BLOCK_H__
  20
  21 /*
  22  * Directory version 2, single block format structures.
  23  *
  24  * The single block format looks like the following drawing on disk:
  25  *
  26  *    +-------------------------------------------------+
  27  *    | xfs_dir2_data_hdr_t                             |
  28  *    +-------------------------------------------------+
  29  *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
  30  *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
  31  *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
  32  *    | ...                                             |
  33  *    +-------------------------------------------------+
  34  *    | unused space                                    |
  35  *    +-------------------------------------------------+
  36  *    | ...                                             |
  37  *    | xfs_dir2_leaf_entry_t                           |
  38  *    | xfs_dir2_leaf_entry_t                           |
  39  *    +-------------------------------------------------+
  40  *    | xfs_dir2_block_tail_t                           |
  41  *    +-------------------------------------------------+
  42  *
  43  * As all the entries are variable size structures the accessors in this
  44  * file and xfs_dir2_data.h should be used to iterate over them.
  45  */
  46 struct uio;
  47 struct xfs_dabuf;
  48 struct xfs_da_args;
  49 struct xfs_dir2_data_hdr;
  50 struct xfs_dir2_leaf_entry;
  51 struct xfs_inode;
  52 struct xfs_mount;
  53 struct xfs_trans;
  54
  55 #define XFS_DIR2_BLOCK_MAGIC    0x58443242      /* XD2B: for one block dirs */
  56
  57 typedef struct xfs_dir2_block_tail {
  58         __be32          count;                  /* count of leaf entries */
  59         __be32          stale;                  /* count of stale lf entries */
  60 } xfs_dir2_block_tail_t;
  61
  62 /*
  63  * Pointer to the leaf header embedded in a data block (1-block format)
  64  */
  65 static inline xfs_dir2_block_tail_t *
  66 xfs_dir2_block_tail_p(struct xfs_mount *mp, xfs_dir2_data_hdr_t *hdr)
  67 {
  68         return ((xfs_dir2_block_tail_t *)((char *)hdr + mp->m_dirblksize)) - 1;
  69 }
  70
  71 /*
  72  * Pointer to the leaf entries embedded in a data block (1-block format)
  73  */
  74 static inline struct xfs_dir2_leaf_entry *
  75 xfs_dir2_block_leaf_p(xfs_dir2_block_tail_t *btp)
  76 {
  77         return ((struct xfs_dir2_leaf_entry *)btp) - be32_to_cpu(btp->count);
  78 }
  79
  80 /*
  81  * Function declarations.
  82  */
  83 extern int xfs_dir2_block_addname(struct xfs_da_args *args);
  84 extern int xfs_dir2_block_getdents(struct xfs_inode *dp, void *dirent,
  85                                    xfs_off_t *offset, filldir_t filldir);
  86 extern int xfs_dir2_block_lookup(struct xfs_da_args *args);
  87 extern int xfs_dir2_block_removename(struct xfs_da_args *args);
  88 extern int xfs_dir2_block_replace(struct xfs_da_args *args);
  89 extern int xfs_dir2_leaf_to_block(struct xfs_da_args *args,
  90                                   struct xfs_dabuf *lbp, struct xfs_dabuf *dbp);
  91 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
  92
  93 #endif  /* __XFS_DIR2_BLOCK_H__ */