LXR linux-old/fs/xfs/xfs_dir2

   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
  42struct uio;
  43struct xfs_dabuf;
  44struct xfs_da_args;
  45struct xfs_dir2_block;
  46struct xfs_inode;
  47struct xfs_mount;
  48struct 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 */
  60typedef struct { __uint8_t i[8]; } xfs_dir2_ino8_t;
  61
  62#define XFS_DIR2_SF_GET_INO8_ARCH(di,arch)      \
  63        (xfs_ino_t)(DIRINO_GET_ARCH(&di,arch))
  64#define XFS_DIR2_SF_GET_INO8(di)                \
  65        XFS_DIR2_SF_GET_INO8_ARCH(di,ARCH_NOCONVERT)
  66
  67/*
  68 * Inode number stored as 4 8-bit values.
  69 * Works a lot of the time, when all the inode numbers in a directory
  70 * fit in 32 bits.
  71 */
  72typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t;
  73#define XFS_DIR2_SF_GET_INO4_ARCH(di,arch)      \
  74        (xfs_ino_t)(DIRINO4_GET_ARCH(&di,arch))
  75#define XFS_DIR2_SF_GET_INO4(di)                \
  76        XFS_DIR2_SF_GET_INO4_ARCH(di,ARCH_NOCONVERT)
  77
  78typedef union {
  79        xfs_dir2_ino8_t i8;
  80        xfs_dir2_ino4_t i4;
  81} xfs_dir2_inou_t;
  82#define XFS_DIR2_MAX_SHORT_INUM ((xfs_ino_t)0xffffffffULL)
  83
  84/*
  85 * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t.
  86 * Only need 16 bits, this is the byte offset into the single block form.
  87 */
  88typedef struct { __uint8_t i[2]; } xfs_dir2_sf_off_t;
  89
  90/*
  91 * The parent directory has a dedicated field, and the self-pointer must
  92 * be calculated on the fly.
  93 *
  94 * Entries are packed toward the top as tightly as possible.  The header
  95 * and the elements must be memcpy'd out into a work area to get correct
  96 * alignment for the inode number fields.
  97 */
  98typedef struct xfs_dir2_sf_hdr {
  99        __uint8_t               count;          /* count of entries */
 100        __uint8_t               i8count;        /* count of 8-byte inode #s */
 101        xfs_dir2_inou_t         parent;         /* parent dir inode number */
 102} xfs_dir2_sf_hdr_t;
 103
 104typedef struct xfs_dir2_sf_entry {
 105        __uint8_t               namelen;        /* actual name length */
 106        xfs_dir2_sf_off_t       offset;         /* saved offset */
 107        __uint8_t               name[1];        /* name, variable size */
 108        xfs_dir2_inou_t         inumber;        /* inode number, var. offset */
 109} xfs_dir2_sf_entry_t;
 110
 111typedef struct xfs_dir2_sf {
 112        xfs_dir2_sf_hdr_t       hdr;            /* shortform header */
 113        xfs_dir2_sf_entry_t     list[1];        /* shortform entries */
 114} xfs_dir2_sf_t;
 115
 116#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_HDR_SIZE)
 117int xfs_dir2_sf_hdr_size(int i8count);
 118#define XFS_DIR2_SF_HDR_SIZE(i8count)   xfs_dir2_sf_hdr_size(i8count)
 119#else
 120#define XFS_DIR2_SF_HDR_SIZE(i8count)   \
 121        ((uint)sizeof(xfs_dir2_sf_hdr_t) - \
 122         ((i8count) == 0) * \
 123         ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)))
 124#endif
 125
 126#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_INUMBERP)
 127xfs_dir2_inou_t *xfs_dir2_sf_inumberp(xfs_dir2_sf_entry_t *sfep);
 128#define XFS_DIR2_SF_INUMBERP(sfep)      xfs_dir2_sf_inumberp(sfep)
 129#else
 130#define XFS_DIR2_SF_INUMBERP(sfep)      \
 131        ((xfs_dir2_inou_t *)&(sfep)->name[(sfep)->namelen])
 132#endif
 133
 134#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_GET_INUMBER)
 135xfs_intino_t xfs_dir2_sf_get_inumber_arch(xfs_dir2_sf_t *sfp, xfs_dir2_inou_t *from,
 136                                            xfs_arch_t arch);
 137#define XFS_DIR2_SF_GET_INUMBER_ARCH(sfp, from, arch)   \
 138        xfs_dir2_sf_get_inumber_arch(sfp, from, arch)
 139
 140#else
 141#define XFS_DIR2_SF_GET_INUMBER_ARCH(sfp, from, arch)   \
 142        ((sfp)->hdr.i8count == 0 ? \
 143                (xfs_intino_t)XFS_DIR2_SF_GET_INO4_ARCH(*(from), arch) : \
 144                (xfs_intino_t)XFS_DIR2_SF_GET_INO8_ARCH(*(from), arch))
 145#endif
 146
 147#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_PUT_INUMBER)
 148void xfs_dir2_sf_put_inumber_arch(xfs_dir2_sf_t *sfp, xfs_ino_t *from,
 149                                     xfs_dir2_inou_t *to, xfs_arch_t arch);
 150#define XFS_DIR2_SF_PUT_INUMBER_ARCH(sfp,from,to,arch)  \
 151        xfs_dir2_sf_put_inumber_arch(sfp,from,to,arch)
 152#else
 153#define XFS_DIR2_SF_PUT_INUMBER_ARCH(sfp,from,to,arch)  \
 154        if ((sfp)->hdr.i8count == 0) { \
 155            DIRINO4_COPY_ARCH(from,to,arch); \
 156        } else { \
 157            DIRINO_COPY_ARCH(from,to,arch); \
 158        }
 159#endif
 160
 161#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_GET_OFFSET)
 162xfs_dir2_data_aoff_t xfs_dir2_sf_get_offset_arch(xfs_dir2_sf_entry_t *sfep,
 163                                                    xfs_arch_t arch);
 164xfs_dir2_data_aoff_t xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep);
 165#define XFS_DIR2_SF_GET_OFFSET_ARCH(sfep,arch)  \
 166        xfs_dir2_sf_get_offset_arch(sfep,arch)
 167#else
 168#define XFS_DIR2_SF_GET_OFFSET_ARCH(sfep,arch)  \
 169        INT_GET_UNALIGNED_16_ARCH(&(sfep)->offset.i,arch)
 170#endif
 171
 172#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_PUT_OFFSET)
 173void xfs_dir2_sf_put_offset_arch(xfs_dir2_sf_entry_t *sfep,
 174                                    xfs_dir2_data_aoff_t off, xfs_arch_t arch);
 175#define XFS_DIR2_SF_PUT_OFFSET_ARCH(sfep,off,arch) \
 176        xfs_dir2_sf_put_offset_arch(sfep,off,arch)
 177#else
 178#define XFS_DIR2_SF_PUT_OFFSET_ARCH(sfep,off,arch)      \
 179        INT_SET_UNALIGNED_16_ARCH(&(sfep)->offset.i,off,arch)
 180#endif
 181
 182#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_ENTSIZE_BYNAME)
 183int xfs_dir2_sf_entsize_byname(xfs_dir2_sf_t *sfp, int len);
 184#define XFS_DIR2_SF_ENTSIZE_BYNAME(sfp,len)     \
 185        xfs_dir2_sf_entsize_byname(sfp,len)
 186#else
 187#define XFS_DIR2_SF_ENTSIZE_BYNAME(sfp,len)     /* space a name uses */ \
 188        ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (len) - \
 189         ((sfp)->hdr.i8count == 0) * \
 190         ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)))
 191#endif
 192
 193#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_ENTSIZE_BYENTRY)
 194int xfs_dir2_sf_entsize_byentry(xfs_dir2_sf_t *sfp, xfs_dir2_sf_entry_t *sfep);
 195#define XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)   \
 196        xfs_dir2_sf_entsize_byentry(sfp,sfep)
 197#else
 198#define XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)   /* space an entry uses */ \
 199        ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (sfep)->namelen - \
 200         ((sfp)->hdr.i8count == 0) * \
 201         ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)))
 202#endif
 203
 204#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_FIRSTENTRY)
 205xfs_dir2_sf_entry_t *xfs_dir2_sf_firstentry(xfs_dir2_sf_t *sfp);
 206#define XFS_DIR2_SF_FIRSTENTRY(sfp)     xfs_dir2_sf_firstentry(sfp)
 207#else
 208#define XFS_DIR2_SF_FIRSTENTRY(sfp)     /* first entry in struct */ \
 209        ((xfs_dir2_sf_entry_t *) \
 210         ((char *)(sfp) + XFS_DIR2_SF_HDR_SIZE(sfp->hdr.i8count)))
 211#endif
 212
 213#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_NEXTENTRY)
 214xfs_dir2_sf_entry_t *xfs_dir2_sf_nextentry(xfs_dir2_sf_t *sfp,
 215                                           xfs_dir2_sf_entry_t *sfep);
 216#define XFS_DIR2_SF_NEXTENTRY(sfp,sfep)         xfs_dir2_sf_nextentry(sfp,sfep)
 217#else
 218#define XFS_DIR2_SF_NEXTENTRY(sfp,sfep)         /* next entry in struct */ \
 219        ((xfs_dir2_sf_entry_t *) \
 220                ((char *)(sfep) + XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)))
 221#endif
 222
 223/*
 224 * Functions.
 225 */
 226
 227extern int
 228        xfs_dir2_block_sfsize(struct xfs_inode *dp,
 229                              struct xfs_dir2_block *block,
 230                              xfs_dir2_sf_hdr_t *sfhp);
 231
 232extern int
 233        xfs_dir2_block_to_sf(struct xfs_da_args *args, struct xfs_dabuf *bp,
 234                             int size, xfs_dir2_sf_hdr_t *sfhp);
 235
 236extern int
 237        xfs_dir2_sf_addname(struct xfs_da_args *args);
 238
 239extern int
 240        xfs_dir2_sf_create(struct xfs_da_args *args, xfs_ino_t pino);
 241
 242extern int
 243        xfs_dir2_sf_getdents(struct xfs_inode *dp, struct uio *uio, int *eofp,
 244                             struct xfs_dirent *dbp, xfs_dir2_put_t put);
 245
 246extern int
 247        xfs_dir2_sf_lookup(struct xfs_da_args *args);
 248
 249extern int
 250        xfs_dir2_sf_removename(struct xfs_da_args *args);
 251
 252extern int
 253        xfs_dir2_sf_replace(struct xfs_da_args *args);
 254
 255#endif  /* __XFS_DIR2_SF_H__ */
 256