fs/xfs/xfs_dir2_sf.h

   1 /*
   2  * Copyright (c) 2000-2001 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_DIR2_SF_H__
  33 #define __XFS_DIR2_SF_H__
  34
  35 /*
  36  * Directory layout when stored internal to an inode.
  37  *
  38  * Small directories are packed as tightly as possible so as to
  39  * fit into the literal area of the inode.
  40  */
  41
  42 struct uio;
  43 struct xfs_dabuf;
  44 struct xfs_da_args;
  45 struct xfs_dir2_block;
  46 struct xfs_inode;
  47 struct xfs_mount;
  48 struct xfs_trans;
  49
  50 /*
  51  * Maximum size of a shortform directory.
  52  */
  53 #define XFS_DIR2_SF_MAX_SIZE    \
  54         (XFS_DINODE_MAX_SIZE - (uint)sizeof(xfs_dinode_core_t) - \
  55          (uint)sizeof(xfs_agino_t))
  56
  57 /*
  58  * Inode number stored as 8 8-bit values.
  59  */
  60 typedef struct { __uint8_t i[8]; } xfs_dir2_ino8_t;
  61
  62 /*
  63  * Inode number stored as 4 8-bit values.
  64  * Works a lot of the time, when all the inode numbers in a directory
  65  * fit in 32 bits.
  66  */
  67 typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t;
  68
  69 typedef union {
  70         xfs_dir2_ino8_t i8;
  71         xfs_dir2_ino4_t i4;
  72 } xfs_dir2_inou_t;
  73 #define XFS_DIR2_MAX_SHORT_INUM ((xfs_ino_t)0xffffffffULL)
  74
  75 /*
  76  * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t.
  77  * Only need 16 bits, this is the byte offset into the single block form.
  78  */
  79 typedef struct { __uint8_t i[2]; } xfs_dir2_sf_off_t;
  80
  81 /*
  82  * The parent directory has a dedicated field, and the self-pointer must
  83  * be calculated on the fly.
  84  *
  85  * Entries are packed toward the top as tightly as possible.  The header
  86  * and the elements must be memcpy'd out into a work area to get correct
  87  * alignment for the inode number fields.
  88  */
  89 typedef struct xfs_dir2_sf_hdr {
  90         __uint8_t               count;          /* count of entries */
  91         __uint8_t               i8count;        /* count of 8-byte inode #s */
  92         xfs_dir2_inou_t         parent;         /* parent dir inode number */
  93 } xfs_dir2_sf_hdr_t;
  94
  95 typedef struct xfs_dir2_sf_entry {
  96         __uint8_t               namelen;        /* actual name length */
  97         xfs_dir2_sf_off_t       offset;         /* saved offset */
  98         __uint8_t               name[1];        /* name, variable size */
  99         xfs_dir2_inou_t         inumber;        /* inode number, var. offset */
 100 } xfs_dir2_sf_entry_t;
 101
 102 typedef struct xfs_dir2_sf {
 103         xfs_dir2_sf_hdr_t       hdr;            /* shortform header */
 104         xfs_dir2_sf_entry_t     list[1];        /* shortform entries */
 105 } xfs_dir2_sf_t;
 106
 107 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_HDR_SIZE)
 108 int xfs_dir2_sf_hdr_size(int i8count);
 109 #define XFS_DIR2_SF_HDR_SIZE(i8count)   xfs_dir2_sf_hdr_size(i8count)
 110 #else
 111 #define XFS_DIR2_SF_HDR_SIZE(i8count)   \
 112         ((uint)sizeof(xfs_dir2_sf_hdr_t) - \
 113          ((i8count) == 0) * \
 114          ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)))
 115 #endif
 116
 117 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_INUMBERP)
 118 xfs_dir2_inou_t *xfs_dir2_sf_inumberp(xfs_dir2_sf_entry_t *sfep);
 119 #define XFS_DIR2_SF_INUMBERP(sfep)      xfs_dir2_sf_inumberp(sfep)
 120 #else
 121 #define XFS_DIR2_SF_INUMBERP(sfep)      \
 122         ((xfs_dir2_inou_t *)&(sfep)->name[(sfep)->namelen])
 123 #endif
 124
 125 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_GET_INUMBER)
 126 xfs_intino_t xfs_dir2_sf_get_inumber(xfs_dir2_sf_t *sfp, xfs_dir2_inou_t *from);
 127 #define XFS_DIR2_SF_GET_INUMBER(sfp, from)      \
 128         xfs_dir2_sf_get_inumber(sfp, from)
 129
 130 #else
 131 #define XFS_DIR2_SF_GET_INUMBER(sfp, from)      \
 132         ((sfp)->hdr.i8count == 0 ? \
 133                 (xfs_intino_t)XFS_GET_DIR_INO4((from)->i4) : \
 134                 (xfs_intino_t)XFS_GET_DIR_INO8((from)->i8))
 135 #endif
 136
 137 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_PUT_INUMBER)
 138 void xfs_dir2_sf_put_inumber(xfs_dir2_sf_t *sfp, xfs_ino_t *from,
 139                                      xfs_dir2_inou_t *to);
 140 #define XFS_DIR2_SF_PUT_INUMBER(sfp,from,to)    \
 141         xfs_dir2_sf_put_inumber(sfp,from,to)
 142 #else
 143 #define XFS_DIR2_SF_PUT_INUMBER(sfp,from,to)    \
 144         if ((sfp)->hdr.i8count == 0) { \
 145                 XFS_PUT_DIR_INO4(*(from), (to)->i4); \
 146         } else { \
 147                 XFS_PUT_DIR_INO8(*(from), (to)->i8); \
 148         }
 149 #endif
 150
 151 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_GET_OFFSET)
 152 xfs_dir2_data_aoff_t xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep);
 153 #define XFS_DIR2_SF_GET_OFFSET(sfep)    \
 154         xfs_dir2_sf_get_offset(sfep)
 155 #else
 156 #define XFS_DIR2_SF_GET_OFFSET(sfep)    \
 157         INT_GET_UNALIGNED_16_BE(&(sfep)->offset.i)
 158 #endif
 159
 160 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_PUT_OFFSET)
 161 void xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep,
 162                                     xfs_dir2_data_aoff_t off);
 163 #define XFS_DIR2_SF_PUT_OFFSET(sfep,off) \
 164         xfs_dir2_sf_put_offset(sfep,off)
 165 #else
 166 #define XFS_DIR2_SF_PUT_OFFSET(sfep,off)        \
 167         INT_SET_UNALIGNED_16_BE(&(sfep)->offset.i,off)
 168 #endif
 169
 170 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_ENTSIZE_BYNAME)
 171 int xfs_dir2_sf_entsize_byname(xfs_dir2_sf_t *sfp, int len);
 172 #define XFS_DIR2_SF_ENTSIZE_BYNAME(sfp,len)     \
 173         xfs_dir2_sf_entsize_byname(sfp,len)
 174 #else
 175 #define XFS_DIR2_SF_ENTSIZE_BYNAME(sfp,len)     /* space a name uses */ \
 176         ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (len) - \
 177          ((sfp)->hdr.i8count == 0) * \
 178          ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)))
 179 #endif
 180
 181 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_ENTSIZE_BYENTRY)
 182 int xfs_dir2_sf_entsize_byentry(xfs_dir2_sf_t *sfp, xfs_dir2_sf_entry_t *sfep);
 183 #define XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)   \
 184         xfs_dir2_sf_entsize_byentry(sfp,sfep)
 185 #else
 186 #define XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)   /* space an entry uses */ \
 187         ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (sfep)->namelen - \
 188          ((sfp)->hdr.i8count == 0) * \
 189          ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)))
 190 #endif
 191
 192 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_FIRSTENTRY)
 193 xfs_dir2_sf_entry_t *xfs_dir2_sf_firstentry(xfs_dir2_sf_t *sfp);
 194 #define XFS_DIR2_SF_FIRSTENTRY(sfp)     xfs_dir2_sf_firstentry(sfp)
 195 #else
 196 #define XFS_DIR2_SF_FIRSTENTRY(sfp)     /* first entry in struct */ \
 197         ((xfs_dir2_sf_entry_t *) \
 198          ((char *)(sfp) + XFS_DIR2_SF_HDR_SIZE(sfp->hdr.i8count)))
 199 #endif
 200
 201 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_NEXTENTRY)
 202 xfs_dir2_sf_entry_t *xfs_dir2_sf_nextentry(xfs_dir2_sf_t *sfp,
 203                                            xfs_dir2_sf_entry_t *sfep);
 204 #define XFS_DIR2_SF_NEXTENTRY(sfp,sfep)         xfs_dir2_sf_nextentry(sfp,sfep)
 205 #else
 206 #define XFS_DIR2_SF_NEXTENTRY(sfp,sfep)         /* next entry in struct */ \
 207         ((xfs_dir2_sf_entry_t *) \
 208                 ((char *)(sfep) + XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)))
 209 #endif
 210
 211 /*
 212  * Functions.
 213  */
 214
 215 extern int
 216         xfs_dir2_block_sfsize(struct xfs_inode *dp,
 217                               struct xfs_dir2_block *block,
 218                               xfs_dir2_sf_hdr_t *sfhp);
 219
 220 extern int
 221         xfs_dir2_block_to_sf(struct xfs_da_args *args, struct xfs_dabuf *bp,
 222                              int size, xfs_dir2_sf_hdr_t *sfhp);
 223
 224 extern int
 225         xfs_dir2_sf_addname(struct xfs_da_args *args);
 226
 227 extern int
 228         xfs_dir2_sf_create(struct xfs_da_args *args, xfs_ino_t pino);
 229
 230 extern int
 231         xfs_dir2_sf_getdents(struct xfs_inode *dp, struct uio *uio, int *eofp,
 232                              struct xfs_dirent *dbp, xfs_dir2_put_t put);
 233
 234 extern int
 235         xfs_dir2_sf_lookup(struct xfs_da_args *args);
 236
 237 extern int
 238         xfs_dir2_sf_removename(struct xfs_da_args *args);
 239
 240 extern int
 241         xfs_dir2_sf_replace(struct xfs_da_args *args);
 242
 243 #endif  /* __XFS_DIR2_SF_H__ */