libxfs/xfs_dir2.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_H__
  19 #define __XFS_DIR2_H__
  20
  21 #include "xfs_da_format.h"
  22 #include "xfs_da_btree.h"
  23
  24 struct xfs_defer_ops;
  25 struct xfs_da_args;
  26 struct xfs_inode;
  27 struct xfs_mount;
  28 struct xfs_trans;
  29 struct xfs_dir2_sf_hdr;
  30 struct xfs_dir2_sf_entry;
  31 struct xfs_dir2_data_hdr;
  32 struct xfs_dir2_data_entry;
  33 struct xfs_dir2_data_unused;
  34
  35 extern struct xfs_name  xfs_name_dotdot;
  36
  37 /*
  38  * Convert inode mode to directory entry filetype
  39  */
  40 extern unsigned char xfs_mode_to_ftype(int mode);
  41
  42 /*
  43  * directory operations vector for encode/decode routines
  44  */
  45 struct xfs_dir_ops {
  46         int     (*sf_entsize)(struct xfs_dir2_sf_hdr *hdr, int len);
  47         struct xfs_dir2_sf_entry *
  48                 (*sf_nextentry)(struct xfs_dir2_sf_hdr *hdr,
  49                                 struct xfs_dir2_sf_entry *sfep);
  50         uint8_t (*sf_get_ftype)(struct xfs_dir2_sf_entry *sfep);
  51         void    (*sf_put_ftype)(struct xfs_dir2_sf_entry *sfep,
  52                                 uint8_t ftype);
  53         xfs_ino_t (*sf_get_ino)(struct xfs_dir2_sf_hdr *hdr,
  54                                 struct xfs_dir2_sf_entry *sfep);
  55         void    (*sf_put_ino)(struct xfs_dir2_sf_hdr *hdr,
  56                               struct xfs_dir2_sf_entry *sfep,
  57                               xfs_ino_t ino);
  58         xfs_ino_t (*sf_get_parent_ino)(struct xfs_dir2_sf_hdr *hdr);
  59         void    (*sf_put_parent_ino)(struct xfs_dir2_sf_hdr *hdr,
  60                                      xfs_ino_t ino);
  61
  62         int     (*data_entsize)(int len);
  63         uint8_t (*data_get_ftype)(struct xfs_dir2_data_entry *dep);
  64         void    (*data_put_ftype)(struct xfs_dir2_data_entry *dep,
  65                                 uint8_t ftype);
  66         __be16 * (*data_entry_tag_p)(struct xfs_dir2_data_entry *dep);
  67         struct xfs_dir2_data_free *
  68                 (*data_bestfree_p)(struct xfs_dir2_data_hdr *hdr);
  69
  70         xfs_dir2_data_aoff_t data_dot_offset;
  71         xfs_dir2_data_aoff_t data_dotdot_offset;
  72         xfs_dir2_data_aoff_t data_first_offset;
  73         size_t  data_entry_offset;
  74
  75         struct xfs_dir2_data_entry *
  76                 (*data_dot_entry_p)(struct xfs_dir2_data_hdr *hdr);
  77         struct xfs_dir2_data_entry *
  78                 (*data_dotdot_entry_p)(struct xfs_dir2_data_hdr *hdr);
  79         struct xfs_dir2_data_entry *
  80                 (*data_first_entry_p)(struct xfs_dir2_data_hdr *hdr);
  81         struct xfs_dir2_data_entry *
  82                 (*data_entry_p)(struct xfs_dir2_data_hdr *hdr);
  83         struct xfs_dir2_data_unused *
  84                 (*data_unused_p)(struct xfs_dir2_data_hdr *hdr);
  85
  86         int     leaf_hdr_size;
  87         void    (*leaf_hdr_to_disk)(struct xfs_dir2_leaf *to,
  88                                     struct xfs_dir3_icleaf_hdr *from);
  89         void    (*leaf_hdr_from_disk)(struct xfs_dir3_icleaf_hdr *to,
  90                                       struct xfs_dir2_leaf *from);
  91         int     (*leaf_max_ents)(struct xfs_da_geometry *geo);
  92         struct xfs_dir2_leaf_entry *
  93                 (*leaf_ents_p)(struct xfs_dir2_leaf *lp);
  94
  95         int     node_hdr_size;
  96         void    (*node_hdr_to_disk)(struct xfs_da_intnode *to,
  97                                     struct xfs_da3_icnode_hdr *from);
  98         void    (*node_hdr_from_disk)(struct xfs_da3_icnode_hdr *to,
  99                                       struct xfs_da_intnode *from);
 100         struct xfs_da_node_entry *
 101                 (*node_tree_p)(struct xfs_da_intnode *dap);
 102
 103         int     free_hdr_size;
 104         void    (*free_hdr_to_disk)(struct xfs_dir2_free *to,
 105                                     struct xfs_dir3_icfree_hdr *from);
 106         void    (*free_hdr_from_disk)(struct xfs_dir3_icfree_hdr *to,
 107                                       struct xfs_dir2_free *from);
 108         int     (*free_max_bests)(struct xfs_da_geometry *geo);
 109         __be16 * (*free_bests_p)(struct xfs_dir2_free *free);
 110         xfs_dir2_db_t (*db_to_fdb)(struct xfs_da_geometry *geo,
 111                                    xfs_dir2_db_t db);
 112         int     (*db_to_fdindex)(struct xfs_da_geometry *geo,
 113                                  xfs_dir2_db_t db);
 114 };
 115
 116 extern const struct xfs_dir_ops *
 117         xfs_dir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
 118 extern const struct xfs_dir_ops *
 119         xfs_nondir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
 120
 121 /*
 122  * Generic directory interface routines
 123  */
 124 extern void xfs_dir_startup(void);
 125 extern int xfs_da_mount(struct xfs_mount *mp);
 126 extern void xfs_da_unmount(struct xfs_mount *mp);
 127
 128 extern int xfs_dir_isempty(struct xfs_inode *dp);
 129 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp,
 130                                 struct xfs_inode *pdp);
 131 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp,
 132                                 struct xfs_name *name, xfs_ino_t inum,
 133                                 xfs_fsblock_t *first,
 134                                 struct xfs_defer_ops *dfops, xfs_extlen_t tot);
 135 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
 136                                 struct xfs_name *name, xfs_ino_t *inum,
 137                                 struct xfs_name *ci_name);
 138 extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
 139                                 struct xfs_name *name, xfs_ino_t ino,
 140                                 xfs_fsblock_t *first,
 141                                 struct xfs_defer_ops *dfops, xfs_extlen_t tot);
 142 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
 143                                 struct xfs_name *name, xfs_ino_t inum,
 144                                 xfs_fsblock_t *first,
 145                                 struct xfs_defer_ops *dfops, xfs_extlen_t tot);
 146 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp,
 147                                 struct xfs_name *name);
 148
 149 /*
 150  * Direct call from the bmap code, bypassing the generic directory layer.
 151  */
 152 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
 153
 154 /*
 155  * Interface routines used by userspace utilities
 156  */
 157 extern int xfs_dir2_isblock(struct xfs_da_args *args, int *r);
 158 extern int xfs_dir2_isleaf(struct xfs_da_args *args, int *r);
 159 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
 160                                 struct xfs_buf *bp);
 161
 162 extern void xfs_dir2_data_freescan_int(struct xfs_da_geometry *geo,
 163                 const struct xfs_dir_ops *ops,
 164                 struct xfs_dir2_data_hdr *hdr, int *loghead);
 165 extern void xfs_dir2_data_freescan(struct xfs_inode *dp,
 166                 struct xfs_dir2_data_hdr *hdr, int *loghead);
 167 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args,
 168                 struct xfs_buf *bp, struct xfs_dir2_data_entry *dep);
 169 extern void xfs_dir2_data_log_header(struct xfs_da_args *args,
 170                 struct xfs_buf *bp);
 171 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args,
 172                 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup);
 173 extern void xfs_dir2_data_make_free(struct xfs_da_args *args,
 174                 struct xfs_buf *bp, xfs_dir2_data_aoff_t offset,
 175                 xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp);
 176 extern void xfs_dir2_data_use_free(struct xfs_da_args *args,
 177                 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup,
 178                 xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len,
 179                 int *needlogp, int *needscanp);
 180
 181 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
 182                 struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
 183                 struct xfs_dir2_data_unused *dup);
 184
 185 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
 186
 187 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
 188 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
 189 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops;
 190 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops;
 191 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops;
 192
 193 /*
 194  * Directory offset/block conversion functions.
 195  *
 196  * DB blocks here are logical directory block numbers, not filesystem blocks.
 197  */
 198
 199 /*
 200  * Convert dataptr to byte in file space
 201  */
 202 static inline xfs_dir2_off_t
 203 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)
 204 {
 205         return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
 206 }
 207
 208 /*
 209  * Convert byte in file space to dataptr.  It had better be aligned.
 210  */
 211 static inline xfs_dir2_dataptr_t
 212 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)
 213 {
 214         return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
 215 }
 216
 217 /*
 218  * Convert byte in space to (DB) block
 219  */
 220 static inline xfs_dir2_db_t
 221 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
 222 {
 223         return (xfs_dir2_db_t)(by >> geo->blklog);
 224 }
 225
 226 /*
 227  * Convert dataptr to a block number
 228  */
 229 static inline xfs_dir2_db_t
 230 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
 231 {
 232         return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp));
 233 }
 234
 235 /*
 236  * Convert byte in space to offset in a block
 237  */
 238 static inline xfs_dir2_data_aoff_t
 239 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
 240 {
 241         return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1));
 242 }
 243
 244 /*
 245  * Convert dataptr to a byte offset in a block
 246  */
 247 static inline xfs_dir2_data_aoff_t
 248 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
 249 {
 250         return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp));
 251 }
 252
 253 /*
 254  * Convert block and offset to byte in space
 255  */
 256 static inline xfs_dir2_off_t
 257 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
 258                         xfs_dir2_data_aoff_t o)
 259 {
 260         return ((xfs_dir2_off_t)db << geo->blklog) + o;
 261 }
 262
 263 /*
 264  * Convert block (DB) to block (dablk)
 265  */
 266 static inline xfs_dablk_t
 267 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
 268 {
 269         return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog));
 270 }
 271
 272 /*
 273  * Convert byte in space to (DA) block
 274  */
 275 static inline xfs_dablk_t
 276 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
 277 {
 278         return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by));
 279 }
 280
 281 /*
 282  * Convert block and offset to dataptr
 283  */
 284 static inline xfs_dir2_dataptr_t
 285 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
 286                            xfs_dir2_data_aoff_t o)
 287 {
 288         return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o));
 289 }
 290
 291 /*
 292  * Convert block (dablk) to block (DB)
 293  */
 294 static inline xfs_dir2_db_t
 295 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da)
 296 {
 297         return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog));
 298 }
 299
 300 /*
 301  * Convert block (dablk) to byte offset in space
 302  */
 303 static inline xfs_dir2_off_t
 304 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da)
 305 {
 306         return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0);
 307 }
 308
 309 /*
 310  * Directory tail pointer accessor functions. Based on block geometry.
 311  */
 312 static inline struct xfs_dir2_block_tail *
 313 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr)
 314 {
 315         return ((struct xfs_dir2_block_tail *)
 316                 ((char *)hdr + geo->blksize)) - 1;
 317 }
 318
 319 static inline struct xfs_dir2_leaf_tail *
 320 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
 321 {
 322         return (struct xfs_dir2_leaf_tail *)
 323                 ((char *)lp + geo->blksize -
 324                   sizeof(struct xfs_dir2_leaf_tail));
 325 }
 326
 327 /*
 328  * The Linux API doesn't pass down the total size of the buffer
 329  * we read into down to the filesystem.  With the filldir concept
 330  * it's not needed for correct information, but the XFS dir2 leaf
 331  * code wants an estimate of the buffer size to calculate it's
 332  * readahead window and size the buffers used for mapping to
 333  * physical blocks.
 334  *
 335  * Try to give it an estimate that's good enough, maybe at some
 336  * point we can change the ->readdir prototype to include the
 337  * buffer size.  For now we use the current glibc buffer size.
 338  * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE.
 339  */
 340 #define XFS_READDIR_BUFSIZE     (32768)
 341
 342 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
 343 void *xfs_dir3_data_endp(struct xfs_da_geometry *geo,
 344                 struct xfs_dir2_data_hdr *hdr);
 345
 346 #endif  /* __XFS_DIR2_H__ */