release/src-rt-6.x.4708/linux/linux-2.6.36/fs/xfs/xfs_dir2_leaf.h

   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
  21 struct uio;
  22 struct xfs_dabuf;
  23 struct xfs_da_args;
  24 struct xfs_inode;
  25 struct xfs_mount;
  26 struct 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  */
  40 typedef __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  */
  47 typedef 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  */
  56 typedef 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  */
  64 typedef 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  */
  73 typedef 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
  85 static 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  */
  94 static inline xfs_dir2_leaf_tail_t *
  95 xfs_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  */
 105 static inline __be16 *
 106 xfs_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  */
 114 static inline xfs_dir2_off_t
 115 xfs_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  */
 123 static inline xfs_dir2_dataptr_t
 124 xfs_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  */
 132 static inline xfs_dir2_db_t
 133 xfs_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  */
 142 static inline xfs_dir2_db_t
 143 xfs_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  */
 151 static inline xfs_dir2_data_aoff_t
 152 xfs_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  */
 161 static inline xfs_dir2_data_aoff_t
 162 xfs_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  */
 170 static inline xfs_dir2_off_t
 171 xfs_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  */
 181 static inline xfs_dablk_t
 182 xfs_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  */
 190 static inline xfs_dablk_t
 191 xfs_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  */
 199 static inline xfs_dir2_dataptr_t
 200 xfs_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  */
 209 static inline xfs_dir2_db_t
 210 xfs_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  */
 218 static inline xfs_dir2_off_t
 219 xfs_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  */
 227 extern int xfs_dir2_block_to_leaf(struct xfs_da_args *args,
 228                                   struct xfs_dabuf *dbp);
 229 extern int xfs_dir2_leaf_addname(struct xfs_da_args *args);
 230 extern void xfs_dir2_leaf_compact(struct xfs_da_args *args,
 231                                   struct xfs_dabuf *bp);
 232 extern void xfs_dir2_leaf_compact_x1(struct xfs_dabuf *bp, int *indexp,
 233                                      int *lowstalep, int *highstalep,
 234                                      int *lowlogp, int *highlogp);
 235 extern int xfs_dir2_leaf_getdents(struct xfs_inode *dp, void *dirent,
 236                                   size_t bufsize, xfs_off_t *offset,
 237                                   filldir_t filldir);
 238 extern int xfs_dir2_leaf_init(struct xfs_da_args *args, xfs_dir2_db_t bno,
 239                               struct xfs_dabuf **bpp, int magic);
 240 extern void xfs_dir2_leaf_log_ents(struct xfs_trans *tp, struct xfs_dabuf *bp,
 241                                    int first, int last);
 242 extern void xfs_dir2_leaf_log_header(struct xfs_trans *tp,
 243                                      struct xfs_dabuf *bp);
 244 extern int xfs_dir2_leaf_lookup(struct xfs_da_args *args);
 245 extern int xfs_dir2_leaf_removename(struct xfs_da_args *args);
 246 extern int xfs_dir2_leaf_replace(struct xfs_da_args *args);
 247 extern int xfs_dir2_leaf_search_hash(struct xfs_da_args *args,
 248                                      struct xfs_dabuf *lbp);
 249 extern int xfs_dir2_leaf_trim_data(struct xfs_da_args *args,
 250                                    struct xfs_dabuf *lbp, xfs_dir2_db_t db);
 251 extern int xfs_dir2_node_to_leaf(struct xfs_da_state *state);
 252
 253 #endif  /* __XFS_DIR2_LEAF_H__ */