LXR linux/fs/xfs/xfs_dir2

   1/*
   2 * Copyright (c) 2000-2001,2005 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_DIR2_LEAF_H__
  19#define __XFS_DIR2_LEAF_H__
  20
  21struct uio;
  22struct xfs_dabuf;
  23struct xfs_da_args;
  24struct xfs_inode;
  25struct xfs_mount;
  26struct xfs_trans;
  27
  28/*
  29 * Offset of the leaf/node space.  First block in this space
  30 * is the btree root.
  31 */
  32#define XFS_DIR2_LEAF_SPACE     1
  33#define XFS_DIR2_LEAF_OFFSET    (XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE)
  34#define XFS_DIR2_LEAF_FIRSTDB(mp)       \
  35        xfs_dir2_byte_to_db(mp, XFS_DIR2_LEAF_OFFSET)
  36
  37/*
  38 * Offset in data space of a data entry.
  39 */
  40typedef __uint32_t      xfs_dir2_dataptr_t;
  41#define XFS_DIR2_MAX_DATAPTR    ((xfs_dir2_dataptr_t)0xffffffff)
  42#define XFS_DIR2_NULL_DATAPTR   ((xfs_dir2_dataptr_t)0)
  43
  44/*
  45 * Leaf block header.
  46 */
  47typedef struct xfs_dir2_leaf_hdr {
  48        xfs_da_blkinfo_t        info;           /* header for da routines */
  49        __be16                  count;          /* count of entries */
  50        __be16                  stale;          /* count of stale entries */
  51} xfs_dir2_leaf_hdr_t;
  52
  53/*
  54 * Leaf block entry.
  55 */
  56typedef struct xfs_dir2_leaf_entry {
  57        __be32                  hashval;        /* hash value of name */
  58        __be32                  address;        /* address of data entry */
  59} xfs_dir2_leaf_entry_t;
  60
  61/*
  62 * Leaf block tail.
  63 */
  64typedef struct xfs_dir2_leaf_tail {
  65        __be32                  bestcount;
  66} xfs_dir2_leaf_tail_t;
  67
  68/*
  69 * Leaf block.
  70 * bests and tail are at the end of the block for single-leaf only
  71 * (magic = XFS_DIR2_LEAF1_MAGIC not XFS_DIR2_LEAFN_MAGIC).
  72 */
  73typedef struct xfs_dir2_leaf {
  74        xfs_dir2_leaf_hdr_t     hdr;            /* leaf header */
  75        xfs_dir2_leaf_entry_t   ents[1];        /* entries */
  76                                                /* ... */
  77        xfs_dir2_data_off_t     bests[1];       /* best free counts */
  78        xfs_dir2_leaf_tail_t    tail;           /* leaf tail */
  79} xfs_dir2_leaf_t;
  80
  81/*
  82 * DB blocks here are logical directory block numbers, not filesystem blocks.
  83 */
  84
  85static inline int xfs_dir2_max_leaf_ents(struct xfs_mount *mp)
  86{
  87        return (int)(((mp)->m_dirblksize - (uint)sizeof(xfs_dir2_leaf_hdr_t)) /
  88               (uint)sizeof(xfs_dir2_leaf_entry_t));
  89}
  90
  91/*
  92 * Get address of the bestcount field in the single-leaf block.
  93 */
  94static inline xfs_dir2_leaf_tail_t *
  95xfs_dir2_leaf_tail_p(struct xfs_mount *mp, xfs_dir2_leaf_t *lp)
  96{
  97        return (xfs_dir2_leaf_tail_t *)
  98                ((char *)(lp) + (mp)->m_dirblksize - 
  99                  (uint)sizeof(xfs_dir2_leaf_tail_t));
 100}
 101
 102/*
 103 * Get address of the bests array in the single-leaf block.
 104 */
 105static inline __be16 *
 106xfs_dir2_leaf_bests_p(xfs_dir2_leaf_tail_t *ltp)
 107{
 108        return (__be16 *)ltp - be32_to_cpu(ltp->bestcount);
 109}
 110
 111/*
 112 * Convert dataptr to byte in file space
 113 */
 114static inline xfs_dir2_off_t
 115xfs_dir2_dataptr_to_byte(struct xfs_mount *mp, xfs_dir2_dataptr_t dp)
 116{
 117        return (xfs_dir2_off_t)(dp) << XFS_DIR2_DATA_ALIGN_LOG;
 118}
 119
 120/*
 121 * Convert byte in file space to dataptr.  It had better be aligned.
 122 */
 123static inline xfs_dir2_dataptr_t
 124xfs_dir2_byte_to_dataptr(struct xfs_mount *mp, xfs_dir2_off_t by)
 125{
 126        return (xfs_dir2_dataptr_t)((by) >> XFS_DIR2_DATA_ALIGN_LOG);
 127}
 128
 129/*
 130 * Convert byte in space to (DB) block
 131 */
 132static inline xfs_dir2_db_t
 133xfs_dir2_byte_to_db(struct xfs_mount *mp, xfs_dir2_off_t by)
 134{
 135        return (xfs_dir2_db_t)((by) >> \
 136                 ((mp)->m_sb.sb_blocklog + (mp)->m_sb.sb_dirblklog));
 137}
 138
 139/*
 140 * Convert dataptr to a block number
 141 */
 142static inline xfs_dir2_db_t
 143xfs_dir2_dataptr_to_db(struct xfs_mount *mp, xfs_dir2_dataptr_t dp)
 144{
 145        return xfs_dir2_byte_to_db(mp, xfs_dir2_dataptr_to_byte(mp, dp));
 146}
 147
 148/*
 149 * Convert byte in space to offset in a block
 150 */
 151static inline xfs_dir2_data_aoff_t
 152xfs_dir2_byte_to_off(struct xfs_mount *mp, xfs_dir2_off_t by)
 153{
 154        return (xfs_dir2_data_aoff_t)((by) & \
 155                ((1 << ((mp)->m_sb.sb_blocklog + (mp)->m_sb.sb_dirblklog)) - 1));
 156}
 157
 158/*
 159 * Convert dataptr to a byte offset in a block
 160 */
 161static inline xfs_dir2_data_aoff_t
 162xfs_dir2_dataptr_to_off(struct xfs_mount *mp, xfs_dir2_dataptr_t dp)
 163{
 164        return xfs_dir2_byte_to_off(mp, xfs_dir2_dataptr_to_byte(mp, dp));
 165}
 166
 167/*
 168 * Convert block and offset to byte in space
 169 */
 170static inline xfs_dir2_off_t
 171xfs_dir2_db_off_to_byte(struct xfs_mount *mp, xfs_dir2_db_t db,
 172                        xfs_dir2_data_aoff_t o)
 173{
 174        return ((xfs_dir2_off_t)(db) << \
 175                ((mp)->m_sb.sb_blocklog + (mp)->m_sb.sb_dirblklog)) + (o);
 176}
 177
 178/*
 179 * Convert block (DB) to block (dablk)
 180 */
 181static inline xfs_dablk_t
 182xfs_dir2_db_to_da(struct xfs_mount *mp, xfs_dir2_db_t db)
 183{
 184        return (xfs_dablk_t)((db) << (mp)->m_sb.sb_dirblklog);
 185}
 186
 187/*
 188 * Convert byte in space to (DA) block
 189 */
 190static inline xfs_dablk_t
 191xfs_dir2_byte_to_da(struct xfs_mount *mp, xfs_dir2_off_t by)
 192{
 193        return xfs_dir2_db_to_da(mp, xfs_dir2_byte_to_db(mp, by));
 194}
 195
 196/*
 197 * Convert block and offset to dataptr
 198 */
 199static inline xfs_dir2_dataptr_t
 200xfs_dir2_db_off_to_dataptr(struct xfs_mount *mp, xfs_dir2_db_t db,
 201                           xfs_dir2_data_aoff_t o)
 202{
 203        return xfs_dir2_byte_to_dataptr(mp, xfs_dir2_db_off_to_byte(mp, db, o));
 204}
 205
 206/*
 207 * Convert block (dablk) to block (DB)
 208 */
 209static inline xfs_dir2_db_t
 210xfs_dir2_da_to_db(struct xfs_mount *mp, xfs_dablk_t da)
 211{
 212        return (xfs_dir2_db_t)((da) >> (mp)->m_sb.sb_dirblklog);
 213}
 214
 215/*
 216 * Convert block (dablk) to byte offset in space
 217 */
 218static inline xfs_dir2_off_t
 219xfs_dir2_da_to_byte(struct xfs_mount *mp, xfs_dablk_t da)
 220{
 221        return xfs_dir2_db_off_to_byte(mp, xfs_dir2_da_to_db(mp, da), 0);
 222}
 223
 224/*
 225 * Function declarations.
 226 */
 227extern int xfs_dir2_block_to_leaf(struct xfs_da_args *args,
 228                                  struct xfs_dabuf *dbp);
 229extern int xfs_dir2_leaf_addname(struct xfs_da_args *args);
 230extern void xfs_dir2_leaf_compact(struct xfs_da_args *args,
 231                                  struct xfs_dabuf *bp);
 232extern void xfs_dir2_leaf_compact_x1(struct xfs_dabuf *bp, int *indexp,
 233                                     int *lowstalep, int *highstalep,
 234                                     int *lowlogp, int *highlogp);
 235extern int xfs_dir2_leaf_getdents(struct xfs_inode *dp, void *dirent,
 236                                  size_t bufsize, xfs_off_t *offset,
 237                                  filldir_t filldir);
 238extern int xfs_dir2_leaf_init(struct xfs_da_args *args, xfs_dir2_db_t bno,
 239                              struct xfs_dabuf **bpp, int magic);
 240extern void xfs_dir2_leaf_log_ents(struct xfs_trans *tp, struct xfs_dabuf *bp,
 241                                   int first, int last);
 242extern void xfs_dir2_leaf_log_header(struct xfs_trans *tp,
 243                                     struct xfs_dabuf *bp);
 244extern int xfs_dir2_leaf_lookup(struct xfs_da_args *args);
 245extern int xfs_dir2_leaf_removename(struct xfs_da_args *args);
 246extern int xfs_dir2_leaf_replace(struct xfs_da_args *args);
 247extern int xfs_dir2_leaf_search_hash(struct xfs_da_args *args,
 248                                     struct xfs_dabuf *lbp);
 249extern int xfs_dir2_leaf_trim_data(struct xfs_da_args *args,
 250                                   struct xfs_dabuf *lbp, xfs_dir2_db_t db);
 251extern int xfs_dir2_node_to_leaf(struct xfs_da_state *state);
 252
 253#endif  /* __XFS_DIR2_LEAF_H__ */
 254