fs/xfs/xfs_dir.h

   1 /*
   2  * Copyright (c) 2000,2005 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_DIR_H__
  19 #define __XFS_DIR_H__
  20
  21 /*
  22  * Large directories are structured around Btrees where all the data
  23  * elements are in the leaf nodes.  Filenames are hashed into an int,
  24  * then that int is used as the index into the Btree.  Since the hashval
  25  * of a filename may not be unique, we may have duplicate keys.  The
  26  * internal links in the Btree are logical block offsets into the file.
  27  *
  28  * Small directories use a different format and are packed as tightly
  29  * as possible so as to fit into the literal area of the inode.
  30  */
  31
  32 /*========================================================================
  33  * Function prototypes for the kernel.
  34  *========================================================================*/
  35
  36 struct uio;
  37 struct xfs_bmap_free;
  38 struct xfs_da_args;
  39 struct xfs_dinode;
  40 struct xfs_inode;
  41 struct xfs_mount;
  42 struct xfs_trans;
  43
  44 /*
  45  * Directory function types.
  46  * Put in structures (xfs_dirops_t) for v1 and v2 directories.
  47  */
  48 typedef void    (*xfs_dir_mount_t)(struct xfs_mount *mp);
  49 typedef int     (*xfs_dir_isempty_t)(struct xfs_inode *dp);
  50 typedef int     (*xfs_dir_init_t)(struct xfs_trans *tp,
  51                                   struct xfs_inode *dp,
  52                                   struct xfs_inode *pdp);
  53 typedef int     (*xfs_dir_createname_t)(struct xfs_trans *tp,
  54                                         struct xfs_inode *dp,
  55                                         char *name,
  56                                         int namelen,
  57                                         xfs_ino_t inum,
  58                                         xfs_fsblock_t *first,
  59                                         struct xfs_bmap_free *flist,
  60                                         xfs_extlen_t total);
  61 typedef int     (*xfs_dir_lookup_t)(struct xfs_trans *tp,
  62                                     struct xfs_inode *dp,
  63                                     char *name,
  64                                     int namelen,
  65                                     xfs_ino_t *inum);
  66 typedef int     (*xfs_dir_removename_t)(struct xfs_trans *tp,
  67                                         struct xfs_inode *dp,
  68                                         char *name,
  69                                         int namelen,
  70                                         xfs_ino_t ino,
  71                                         xfs_fsblock_t *first,
  72                                         struct xfs_bmap_free *flist,
  73                                         xfs_extlen_t total);
  74 typedef int     (*xfs_dir_getdents_t)(struct xfs_trans *tp,
  75                                       struct xfs_inode *dp,
  76                                       struct uio *uio,
  77                                       int *eofp);
  78 typedef int     (*xfs_dir_replace_t)(struct xfs_trans *tp,
  79                                      struct xfs_inode *dp,
  80                                      char *name,
  81                                      int namelen,
  82                                      xfs_ino_t inum,
  83                                      xfs_fsblock_t *first,
  84                                      struct xfs_bmap_free *flist,
  85                                      xfs_extlen_t total);
  86 typedef int     (*xfs_dir_canenter_t)(struct xfs_trans *tp,
  87                                       struct xfs_inode *dp,
  88                                       char *name,
  89                                       int namelen);
  90 typedef int     (*xfs_dir_shortform_validate_ondisk_t)(struct xfs_mount *mp,
  91                                                        struct xfs_dinode *dip);
  92 typedef int     (*xfs_dir_shortform_to_single_t)(struct xfs_da_args *args);
  93
  94 typedef struct xfs_dirops {
  95         xfs_dir_mount_t                         xd_mount;
  96         xfs_dir_isempty_t                       xd_isempty;
  97         xfs_dir_init_t                          xd_init;
  98         xfs_dir_createname_t                    xd_createname;
  99         xfs_dir_lookup_t                        xd_lookup;
 100         xfs_dir_removename_t                    xd_removename;
 101         xfs_dir_getdents_t                      xd_getdents;
 102         xfs_dir_replace_t                       xd_replace;
 103         xfs_dir_canenter_t                      xd_canenter;
 104         xfs_dir_shortform_validate_ondisk_t     xd_shortform_validate_ondisk;
 105         xfs_dir_shortform_to_single_t           xd_shortform_to_single;
 106 } xfs_dirops_t;
 107
 108 /*
 109  * Overall external interface routines.
 110  */
 111 void    xfs_dir_startup(void);  /* called exactly once */
 112
 113 #define XFS_DIR_MOUNT(mp)       \
 114         ((mp)->m_dirops.xd_mount(mp))
 115 #define XFS_DIR_ISEMPTY(mp,dp)  \
 116         ((mp)->m_dirops.xd_isempty(dp))
 117 #define XFS_DIR_INIT(mp,tp,dp,pdp)      \
 118         ((mp)->m_dirops.xd_init(tp,dp,pdp))
 119 #define XFS_DIR_CREATENAME(mp,tp,dp,name,namelen,inum,first,flist,total) \
 120         ((mp)->m_dirops.xd_createname(tp,dp,name,namelen,inum,first,flist,\
 121                                       total))
 122 #define XFS_DIR_LOOKUP(mp,tp,dp,name,namelen,inum)      \
 123         ((mp)->m_dirops.xd_lookup(tp,dp,name,namelen,inum))
 124 #define XFS_DIR_REMOVENAME(mp,tp,dp,name,namelen,ino,first,flist,total) \
 125         ((mp)->m_dirops.xd_removename(tp,dp,name,namelen,ino,first,flist,total))
 126 #define XFS_DIR_GETDENTS(mp,tp,dp,uio,eofp)     \
 127         ((mp)->m_dirops.xd_getdents(tp,dp,uio,eofp))
 128 #define XFS_DIR_REPLACE(mp,tp,dp,name,namelen,inum,first,flist,total)   \
 129         ((mp)->m_dirops.xd_replace(tp,dp,name,namelen,inum,first,flist,total))
 130 #define XFS_DIR_CANENTER(mp,tp,dp,name,namelen) \
 131         ((mp)->m_dirops.xd_canenter(tp,dp,name,namelen))
 132 #define XFS_DIR_SHORTFORM_VALIDATE_ONDISK(mp,dip)       \
 133         ((mp)->m_dirops.xd_shortform_validate_ondisk(mp,dip))
 134 #define XFS_DIR_SHORTFORM_TO_SINGLE(mp,args)    \
 135         ((mp)->m_dirops.xd_shortform_to_single(args))
 136
 137 #define XFS_DIR_IS_V1(mp)       ((mp)->m_dirversion == 1)
 138 extern xfs_dirops_t xfsv1_dirops;
 139
 140 #endif  /* __XFS_DIR_H__ */