libxfs/xfs_dir2.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
   4  * All Rights Reserved.
   5  */
   6 #ifndef __XFS_DIR2_H__
   7 #define __XFS_DIR2_H__
   8
   9 #include "xfs_da_format.h"
  10 #include "xfs_da_btree.h"
  11
  12 struct xfs_defer_ops;
  13 struct xfs_da_args;
  14 struct xfs_inode;
  15 struct xfs_mount;
  16 struct xfs_trans;
  17 struct xfs_dir2_sf_hdr;
  18 struct xfs_dir2_sf_entry;
  19 struct xfs_dir2_data_hdr;
  20 struct xfs_dir2_data_entry;
  21 struct xfs_dir2_data_unused;
  22
  23 extern struct xfs_name  xfs_name_dotdot;
  24
  25 /*
  26  * Convert inode mode to directory entry filetype
  27  */
  28 extern unsigned char xfs_mode_to_ftype(int mode);
  29
  30 /*
  31  * directory operations vector for encode/decode routines
  32  */
  33 struct xfs_dir_ops {
  34         int     (*sf_entsize)(struct xfs_dir2_sf_hdr *hdr, int len);
  35         struct xfs_dir2_sf_entry *
  36                 (*sf_nextentry)(struct xfs_dir2_sf_hdr *hdr,
  37                                 struct xfs_dir2_sf_entry *sfep);
  38         uint8_t (*sf_get_ftype)(struct xfs_dir2_sf_entry *sfep);
  39         void    (*sf_put_ftype)(struct xfs_dir2_sf_entry *sfep,
  40                                 uint8_t ftype);
  41         xfs_ino_t (*sf_get_ino)(struct xfs_dir2_sf_hdr *hdr,
  42                                 struct xfs_dir2_sf_entry *sfep);
  43         void    (*sf_put_ino)(struct xfs_dir2_sf_hdr *hdr,
  44                               struct xfs_dir2_sf_entry *sfep,
  45                               xfs_ino_t ino);
  46         xfs_ino_t (*sf_get_parent_ino)(struct xfs_dir2_sf_hdr *hdr);
  47         void    (*sf_put_parent_ino)(struct xfs_dir2_sf_hdr *hdr,
  48                                      xfs_ino_t ino);
  49
  50         int     (*data_entsize)(int len);
  51         uint8_t (*data_get_ftype)(struct xfs_dir2_data_entry *dep);
  52         void    (*data_put_ftype)(struct xfs_dir2_data_entry *dep,
  53                                 uint8_t ftype);
  54         __be16 * (*data_entry_tag_p)(struct xfs_dir2_data_entry *dep);
  55         struct xfs_dir2_data_free *
  56                 (*data_bestfree_p)(struct xfs_dir2_data_hdr *hdr);
  57
  58         xfs_dir2_data_aoff_t data_dot_offset;
  59         xfs_dir2_data_aoff_t data_dotdot_offset;
  60         xfs_dir2_data_aoff_t data_first_offset;
  61         size_t  data_entry_offset;
  62
  63         struct xfs_dir2_data_entry *
  64                 (*data_dot_entry_p)(struct xfs_dir2_data_hdr *hdr);
  65         struct xfs_dir2_data_entry *
  66                 (*data_dotdot_entry_p)(struct xfs_dir2_data_hdr *hdr);
  67         struct xfs_dir2_data_entry *
  68                 (*data_first_entry_p)(struct xfs_dir2_data_hdr *hdr);
  69         struct xfs_dir2_data_entry *
  70                 (*data_entry_p)(struct xfs_dir2_data_hdr *hdr);
  71         struct xfs_dir2_data_unused *
  72                 (*data_unused_p)(struct xfs_dir2_data_hdr *hdr);
  73
  74         int     leaf_hdr_size;
  75         void    (*leaf_hdr_to_disk)(struct xfs_dir2_leaf *to,
  76                                     struct xfs_dir3_icleaf_hdr *from);
  77         void    (*leaf_hdr_from_disk)(struct xfs_dir3_icleaf_hdr *to,
  78                                       struct xfs_dir2_leaf *from);
  79         int     (*leaf_max_ents)(struct xfs_da_geometry *geo);
  80         struct xfs_dir2_leaf_entry *
  81                 (*leaf_ents_p)(struct xfs_dir2_leaf *lp);
  82
  83         int     node_hdr_size;
  84         void    (*node_hdr_to_disk)(struct xfs_da_intnode *to,
  85                                     struct xfs_da3_icnode_hdr *from);
  86         void    (*node_hdr_from_disk)(struct xfs_da3_icnode_hdr *to,
  87                                       struct xfs_da_intnode *from);
  88         struct xfs_da_node_entry *
  89                 (*node_tree_p)(struct xfs_da_intnode *dap);
  90
  91         int     free_hdr_size;
  92         void    (*free_hdr_to_disk)(struct xfs_dir2_free *to,
  93                                     struct xfs_dir3_icfree_hdr *from);
  94         void    (*free_hdr_from_disk)(struct xfs_dir3_icfree_hdr *to,
  95                                       struct xfs_dir2_free *from);
  96         int     (*free_max_bests)(struct xfs_da_geometry *geo);
  97         __be16 * (*free_bests_p)(struct xfs_dir2_free *free);
  98         xfs_dir2_db_t (*db_to_fdb)(struct xfs_da_geometry *geo,
  99                                    xfs_dir2_db_t db);
 100         int     (*db_to_fdindex)(struct xfs_da_geometry *geo,
 101                                  xfs_dir2_db_t db);
 102 };
 103
 104 extern const struct xfs_dir_ops *
 105         xfs_dir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
 106 extern const struct xfs_dir_ops *
 107         xfs_nondir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
 108
 109 /*
 110  * Generic directory interface routines
 111  */
 112 extern void xfs_dir_startup(void);
 113 extern int xfs_da_mount(struct xfs_mount *mp);
 114 extern void xfs_da_unmount(struct xfs_mount *mp);
 115
 116 extern int xfs_dir_isempty(struct xfs_inode *dp);
 117 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp,
 118                                 struct xfs_inode *pdp);
 119 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp,
 120                                 struct xfs_name *name, xfs_ino_t inum,
 121                                 xfs_fsblock_t *first, xfs_extlen_t tot);
 122 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
 123                                 struct xfs_name *name, xfs_ino_t *inum,
 124                                 struct xfs_name *ci_name);
 125 extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
 126                                 struct xfs_name *name, xfs_ino_t ino,
 127                                 xfs_fsblock_t *first, xfs_extlen_t tot);
 128 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
 129                                 struct xfs_name *name, xfs_ino_t inum,
 130                                 xfs_fsblock_t *first, xfs_extlen_t tot);
 131 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp,
 132                                 struct xfs_name *name);
 133
 134 /*
 135  * Direct call from the bmap code, bypassing the generic directory layer.
 136  */
 137 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
 138
 139 /*
 140  * Interface routines used by userspace utilities
 141  */
 142 extern int xfs_dir2_isblock(struct xfs_da_args *args, int *r);
 143 extern int xfs_dir2_isleaf(struct xfs_da_args *args, int *r);
 144 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
 145                                 struct xfs_buf *bp);
 146
 147 extern void xfs_dir2_data_freescan_int(struct xfs_da_geometry *geo,
 148                 const struct xfs_dir_ops *ops,
 149                 struct xfs_dir2_data_hdr *hdr, int *loghead);
 150 extern void xfs_dir2_data_freescan(struct xfs_inode *dp,
 151                 struct xfs_dir2_data_hdr *hdr, int *loghead);
 152 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args,
 153                 struct xfs_buf *bp, struct xfs_dir2_data_entry *dep);
 154 extern void xfs_dir2_data_log_header(struct xfs_da_args *args,
 155                 struct xfs_buf *bp);
 156 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args,
 157                 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup);
 158 extern void xfs_dir2_data_make_free(struct xfs_da_args *args,
 159                 struct xfs_buf *bp, xfs_dir2_data_aoff_t offset,
 160                 xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp);
 161 extern int xfs_dir2_data_use_free(struct xfs_da_args *args,
 162                 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup,
 163                 xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len,
 164                 int *needlogp, int *needscanp);
 165
 166 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
 167                 struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
 168                 struct xfs_dir2_data_unused *dup);
 169
 170 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
 171
 172 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
 173 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
 174 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops;
 175 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops;
 176 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops;
 177
 178 /*
 179  * Directory offset/block conversion functions.
 180  *
 181  * DB blocks here are logical directory block numbers, not filesystem blocks.
 182  */
 183
 184 /*
 185  * Convert dataptr to byte in file space
 186  */
 187 static inline xfs_dir2_off_t
 188 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)
 189 {
 190         return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
 191 }
 192
 193 /*
 194  * Convert byte in file space to dataptr.  It had better be aligned.
 195  */
 196 static inline xfs_dir2_dataptr_t
 197 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)
 198 {
 199         return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
 200 }
 201
 202 /*
 203  * Convert byte in space to (DB) block
 204  */
 205 static inline xfs_dir2_db_t
 206 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
 207 {
 208         return (xfs_dir2_db_t)(by >> geo->blklog);
 209 }
 210
 211 /*
 212  * Convert dataptr to a block number
 213  */
 214 static inline xfs_dir2_db_t
 215 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
 216 {
 217         return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp));
 218 }
 219
 220 /*
 221  * Convert byte in space to offset in a block
 222  */
 223 static inline xfs_dir2_data_aoff_t
 224 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
 225 {
 226         return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1));
 227 }
 228
 229 /*
 230  * Convert dataptr to a byte offset in a block
 231  */
 232 static inline xfs_dir2_data_aoff_t
 233 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
 234 {
 235         return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp));
 236 }
 237
 238 /*
 239  * Convert block and offset to byte in space
 240  */
 241 static inline xfs_dir2_off_t
 242 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
 243                         xfs_dir2_data_aoff_t o)
 244 {
 245         return ((xfs_dir2_off_t)db << geo->blklog) + o;
 246 }
 247
 248 /*
 249  * Convert block (DB) to block (dablk)
 250  */
 251 static inline xfs_dablk_t
 252 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
 253 {
 254         return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog));
 255 }
 256
 257 /*
 258  * Convert byte in space to (DA) block
 259  */
 260 static inline xfs_dablk_t
 261 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
 262 {
 263         return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by));
 264 }
 265
 266 /*
 267  * Convert block and offset to dataptr
 268  */
 269 static inline xfs_dir2_dataptr_t
 270 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
 271                            xfs_dir2_data_aoff_t o)
 272 {
 273         return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o));
 274 }
 275
 276 /*
 277  * Convert block (dablk) to block (DB)
 278  */
 279 static inline xfs_dir2_db_t
 280 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da)
 281 {
 282         return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog));
 283 }
 284
 285 /*
 286  * Convert block (dablk) to byte offset in space
 287  */
 288 static inline xfs_dir2_off_t
 289 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da)
 290 {
 291         return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0);
 292 }
 293
 294 /*
 295  * Directory tail pointer accessor functions. Based on block geometry.
 296  */
 297 static inline struct xfs_dir2_block_tail *
 298 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr)
 299 {
 300         return ((struct xfs_dir2_block_tail *)
 301                 ((char *)hdr + geo->blksize)) - 1;
 302 }
 303
 304 static inline struct xfs_dir2_leaf_tail *
 305 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
 306 {
 307         return (struct xfs_dir2_leaf_tail *)
 308                 ((char *)lp + geo->blksize -
 309                   sizeof(struct xfs_dir2_leaf_tail));
 310 }
 311
 312 /*
 313  * The Linux API doesn't pass down the total size of the buffer
 314  * we read into down to the filesystem.  With the filldir concept
 315  * it's not needed for correct information, but the XFS dir2 leaf
 316  * code wants an estimate of the buffer size to calculate it's
 317  * readahead window and size the buffers used for mapping to
 318  * physical blocks.
 319  *
 320  * Try to give it an estimate that's good enough, maybe at some
 321  * point we can change the ->readdir prototype to include the
 322  * buffer size.  For now we use the current glibc buffer size.
 323  * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE.
 324  */
 325 #define XFS_READDIR_BUFSIZE     (32768)
 326
 327 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
 328 void *xfs_dir3_data_endp(struct xfs_da_geometry *geo,
 329                 struct xfs_dir2_data_hdr *hdr);
 330
 331 #endif  /* __XFS_DIR2_H__ */