LXR linux-old/fs/xfs/xfs

   1/*
   2 * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or modify it
   5 * under the terms of version 2 of the GNU General Public License as
   6 * published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it would be useful, but
   9 * WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11 *
  12 * Further, this software is distributed without any warranty that it is
  13 * free of the rightful claim of any third person regarding infringement
  14 * or the like.  Any license provided herein, whether implied or
  15 * otherwise, applies only to this software file.  Patent licenses, if
  16 * any, provided herein do not apply to combinations of this program with
  17 * other software, or any other product whatsoever.
  18 *
  19 * You should have received a copy of the GNU General Public License along
  20 * with this program; if not, write the Free Software Foundation, Inc., 59
  21 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22 *
  23 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
  24 * Mountain View, CA  94043, or:
  25 *
  26 * http://www.sgi.com
  27 *
  28 * For further information regarding this notice, see:
  29 *
  30 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  31 */
  32#ifndef __XFS_DIR_H__
  33#define __XFS_DIR_H__
  34
  35/*
  36 * Large directories are structured around Btrees where all the data
  37 * elements are in the leaf nodes.  Filenames are hashed into an int,
  38 * then that int is used as the index into the Btree.  Since the hashval
  39 * of a filename may not be unique, we may have duplicate keys.  The
  40 * internal links in the Btree are logical block offsets into the file.
  41 *
  42 * Small directories use a different format and are packed as tightly
  43 * as possible so as to fit into the literal area of the inode.
  44 */
  45
  46/*========================================================================
  47 * Function prototypes for the kernel.
  48 *========================================================================*/
  49
  50struct uio;
  51struct xfs_bmap_free;
  52struct xfs_da_args;
  53struct xfs_dinode;
  54struct xfs_inode;
  55struct xfs_mount;
  56struct xfs_trans;
  57
  58/*
  59 * Directory function types.
  60 * Put in structures (xfs_dirops_t) for v1 and v2 directories.
  61 */
  62typedef void    (*xfs_dir_mount_t)(struct xfs_mount *mp);
  63typedef int     (*xfs_dir_isempty_t)(struct xfs_inode *dp);
  64typedef int     (*xfs_dir_init_t)(struct xfs_trans *tp,
  65                                  struct xfs_inode *dp,
  66                                  struct xfs_inode *pdp);
  67typedef int     (*xfs_dir_createname_t)(struct xfs_trans *tp,
  68                                        struct xfs_inode *dp,
  69                                        char *name,
  70                                        int namelen,
  71                                        xfs_ino_t inum,
  72                                        xfs_fsblock_t *first,
  73                                        struct xfs_bmap_free *flist,
  74                                        xfs_extlen_t total);
  75typedef int     (*xfs_dir_lookup_t)(struct xfs_trans *tp,
  76                                    struct xfs_inode *dp,
  77                                    char *name,
  78                                    int namelen,
  79                                    xfs_ino_t *inum);
  80typedef int     (*xfs_dir_removename_t)(struct xfs_trans *tp,
  81                                        struct xfs_inode *dp,
  82                                        char *name,
  83                                        int namelen,
  84                                        xfs_ino_t ino,
  85                                        xfs_fsblock_t *first,
  86                                        struct xfs_bmap_free *flist,
  87                                        xfs_extlen_t total);
  88typedef int     (*xfs_dir_getdents_t)(struct xfs_trans *tp,
  89                                      struct xfs_inode *dp,
  90                                      struct uio *uio,
  91                                      int *eofp);
  92typedef int     (*xfs_dir_replace_t)(struct xfs_trans *tp,
  93                                     struct xfs_inode *dp,
  94                                     char *name,
  95                                     int namelen,
  96                                     xfs_ino_t inum,
  97                                     xfs_fsblock_t *first,
  98                                     struct xfs_bmap_free *flist,
  99                                     xfs_extlen_t total);
 100typedef int     (*xfs_dir_canenter_t)(struct xfs_trans *tp,
 101                                      struct xfs_inode *dp,
 102                                      char *name,
 103                                      int namelen);
 104typedef int     (*xfs_dir_shortform_validate_ondisk_t)(struct xfs_mount *mp,
 105                                                       struct xfs_dinode *dip);
 106typedef int     (*xfs_dir_shortform_to_single_t)(struct xfs_da_args *args);
 107
 108typedef struct xfs_dirops {
 109        xfs_dir_mount_t                         xd_mount;
 110        xfs_dir_isempty_t                       xd_isempty;
 111        xfs_dir_init_t                          xd_init;
 112        xfs_dir_createname_t                    xd_createname;
 113        xfs_dir_lookup_t                        xd_lookup;
 114        xfs_dir_removename_t                    xd_removename;
 115        xfs_dir_getdents_t                      xd_getdents;
 116        xfs_dir_replace_t                       xd_replace;
 117        xfs_dir_canenter_t                      xd_canenter;
 118        xfs_dir_shortform_validate_ondisk_t     xd_shortform_validate_ondisk;
 119        xfs_dir_shortform_to_single_t           xd_shortform_to_single;
 120} xfs_dirops_t;
 121
 122/*
 123 * Overall external interface routines.
 124 */
 125void    xfs_dir_startup(void);  /* called exactly once */
 126
 127#define XFS_DIR_MOUNT(mp)       \
 128        ((mp)->m_dirops.xd_mount(mp))
 129#define XFS_DIR_ISEMPTY(mp,dp)  \
 130        ((mp)->m_dirops.xd_isempty(dp))
 131#define XFS_DIR_INIT(mp,tp,dp,pdp)      \
 132        ((mp)->m_dirops.xd_init(tp,dp,pdp))
 133#define XFS_DIR_CREATENAME(mp,tp,dp,name,namelen,inum,first,flist,total) \
 134        ((mp)->m_dirops.xd_createname(tp,dp,name,namelen,inum,first,flist,\
 135                                      total))
 136#define XFS_DIR_LOOKUP(mp,tp,dp,name,namelen,inum)      \
 137        ((mp)->m_dirops.xd_lookup(tp,dp,name,namelen,inum))
 138#define XFS_DIR_REMOVENAME(mp,tp,dp,name,namelen,ino,first,flist,total) \
 139        ((mp)->m_dirops.xd_removename(tp,dp,name,namelen,ino,first,flist,total))
 140#define XFS_DIR_GETDENTS(mp,tp,dp,uio,eofp)     \
 141        ((mp)->m_dirops.xd_getdents(tp,dp,uio,eofp))
 142#define XFS_DIR_REPLACE(mp,tp,dp,name,namelen,inum,first,flist,total)   \
 143        ((mp)->m_dirops.xd_replace(tp,dp,name,namelen,inum,first,flist,total))
 144#define XFS_DIR_CANENTER(mp,tp,dp,name,namelen) \
 145        ((mp)->m_dirops.xd_canenter(tp,dp,name,namelen))
 146#define XFS_DIR_SHORTFORM_VALIDATE_ONDISK(mp,dip)       \
 147        ((mp)->m_dirops.xd_shortform_validate_ondisk(mp,dip))
 148#define XFS_DIR_SHORTFORM_TO_SINGLE(mp,args)    \
 149        ((mp)->m_dirops.xd_shortform_to_single(args))
 150
 151#define XFS_DIR_IS_V1(mp)       ((mp)->m_dirversion == 1)
 152extern xfs_dirops_t xfsv1_dirops;
 153
 154#endif  /* __XFS_DIR_H__ */
 155