fs/xfs/xfs_dir.h

   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
  50 struct uio;
  51 struct xfs_bmap_free;
  52 struct xfs_da_args;
  53 struct xfs_dinode;
  54 struct xfs_inode;
  55 struct xfs_mount;
  56 struct xfs_trans;
  57
  58 /*
  59  * Directory function types.
  60  * Put in structures (xfs_dirops_t) for v1 and v2 directories.
  61  */
  62 typedef void    (*xfs_dir_mount_t)(struct xfs_mount *mp);
  63 typedef int     (*xfs_dir_isempty_t)(struct xfs_inode *dp);
  64 typedef int     (*xfs_dir_init_t)(struct xfs_trans *tp,
  65                                   struct xfs_inode *dp,
  66                                   struct xfs_inode *pdp);
  67 typedef 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);
  75 typedef 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);
  80 typedef 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);
  88 typedef int     (*xfs_dir_getdents_t)(struct xfs_trans *tp,
  89                                       struct xfs_inode *dp,
  90                                       struct uio *uio,
  91                                       int *eofp);
  92 typedef 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);
 100 typedef int     (*xfs_dir_canenter_t)(struct xfs_trans *tp,
 101                                       struct xfs_inode *dp,
 102                                       char *name,
 103                                       int namelen);
 104 typedef int     (*xfs_dir_shortform_validate_ondisk_t)(struct xfs_mount *mp,
 105                                                        struct xfs_dinode *dip);
 106 typedef int     (*xfs_dir_shortform_to_single_t)(struct xfs_da_args *args);
 107
 108 typedef 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  */
 125 void    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)
 152 extern xfs_dirops_t xfsv1_dirops;
 153
 154 #endif  /* __XFS_DIR_H__ */