LXR linux/fs/xfs/libxfs/xfs

   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
  12struct xfs_da_args;
  13struct xfs_inode;
  14struct xfs_mount;
  15struct xfs_trans;
  16struct xfs_dir2_sf_hdr;
  17struct xfs_dir2_sf_entry;
  18struct xfs_dir2_data_hdr;
  19struct xfs_dir2_data_entry;
  20struct xfs_dir2_data_unused;
  21struct xfs_dir3_icfree_hdr;
  22struct xfs_dir3_icleaf_hdr;
  23
  24extern struct xfs_name  xfs_name_dotdot;
  25
  26/*
  27 * Convert inode mode to directory entry filetype
  28 */
  29extern unsigned char xfs_mode_to_ftype(int mode);
  30
  31/*
  32 * Generic directory interface routines
  33 */
  34extern void xfs_dir_startup(void);
  35extern int xfs_da_mount(struct xfs_mount *mp);
  36extern void xfs_da_unmount(struct xfs_mount *mp);
  37
  38extern int xfs_dir_isempty(struct xfs_inode *dp);
  39extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp,
  40                                struct xfs_inode *pdp);
  41extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp,
  42                                struct xfs_name *name, xfs_ino_t inum,
  43                                xfs_extlen_t tot);
  44extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
  45                                struct xfs_name *name, xfs_ino_t *inum,
  46                                struct xfs_name *ci_name);
  47extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
  48                                struct xfs_name *name, xfs_ino_t ino,
  49                                xfs_extlen_t tot);
  50extern bool xfs_dir2_sf_replace_needblock(struct xfs_inode *dp,
  51                                xfs_ino_t inum);
  52extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
  53                                struct xfs_name *name, xfs_ino_t inum,
  54                                xfs_extlen_t tot);
  55extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp,
  56                                struct xfs_name *name);
  57
  58/*
  59 * Direct call from the bmap code, bypassing the generic directory layer.
  60 */
  61extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
  62
  63/*
  64 * Interface routines used by userspace utilities
  65 */
  66extern int xfs_dir2_isblock(struct xfs_da_args *args, int *r);
  67extern int xfs_dir2_isleaf(struct xfs_da_args *args, int *r);
  68extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
  69                                struct xfs_buf *bp);
  70
  71extern void xfs_dir2_data_freescan(struct xfs_mount *mp,
  72                struct xfs_dir2_data_hdr *hdr, int *loghead);
  73extern void xfs_dir2_data_log_entry(struct xfs_da_args *args,
  74                struct xfs_buf *bp, struct xfs_dir2_data_entry *dep);
  75extern void xfs_dir2_data_log_header(struct xfs_da_args *args,
  76                struct xfs_buf *bp);
  77extern void xfs_dir2_data_log_unused(struct xfs_da_args *args,
  78                struct xfs_buf *bp, struct xfs_dir2_data_unused *dup);
  79extern void xfs_dir2_data_make_free(struct xfs_da_args *args,
  80                struct xfs_buf *bp, xfs_dir2_data_aoff_t offset,
  81                xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp);
  82extern int xfs_dir2_data_use_free(struct xfs_da_args *args,
  83                struct xfs_buf *bp, struct xfs_dir2_data_unused *dup,
  84                xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len,
  85                int *needlogp, int *needscanp);
  86
  87extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
  88                struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
  89                struct xfs_dir2_data_unused *dup);
  90
  91extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
  92
  93extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
  94extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
  95extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops;
  96extern const struct xfs_buf_ops xfs_dir3_free_buf_ops;
  97extern const struct xfs_buf_ops xfs_dir3_data_buf_ops;
  98
  99/*
 100 * Directory offset/block conversion functions.
 101 *
 102 * DB blocks here are logical directory block numbers, not filesystem blocks.
 103 */
 104
 105/*
 106 * Convert dataptr to byte in file space
 107 */
 108static inline xfs_dir2_off_t
 109xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)
 110{
 111        return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
 112}
 113
 114/*
 115 * Convert byte in file space to dataptr.  It had better be aligned.
 116 */
 117static inline xfs_dir2_dataptr_t
 118xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)
 119{
 120        return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
 121}
 122
 123/*
 124 * Convert byte in space to (DB) block
 125 */
 126static inline xfs_dir2_db_t
 127xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
 128{
 129        return (xfs_dir2_db_t)(by >> geo->blklog);
 130}
 131
 132/*
 133 * Convert dataptr to a block number
 134 */
 135static inline xfs_dir2_db_t
 136xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
 137{
 138        return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp));
 139}
 140
 141/*
 142 * Convert byte in space to offset in a block
 143 */
 144static inline xfs_dir2_data_aoff_t
 145xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
 146{
 147        return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1));
 148}
 149
 150/*
 151 * Convert dataptr to a byte offset in a block
 152 */
 153static inline xfs_dir2_data_aoff_t
 154xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
 155{
 156        return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp));
 157}
 158
 159/*
 160 * Convert block and offset to byte in space
 161 */
 162static inline xfs_dir2_off_t
 163xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
 164                        xfs_dir2_data_aoff_t o)
 165{
 166        return ((xfs_dir2_off_t)db << geo->blklog) + o;
 167}
 168
 169/*
 170 * Convert block (DB) to block (dablk)
 171 */
 172static inline xfs_dablk_t
 173xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
 174{
 175        return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog));
 176}
 177
 178/*
 179 * Convert byte in space to (DA) block
 180 */
 181static inline xfs_dablk_t
 182xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
 183{
 184        return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by));
 185}
 186
 187/*
 188 * Convert block and offset to dataptr
 189 */
 190static inline xfs_dir2_dataptr_t
 191xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
 192                           xfs_dir2_data_aoff_t o)
 193{
 194        return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o));
 195}
 196
 197/*
 198 * Convert block (dablk) to block (DB)
 199 */
 200static inline xfs_dir2_db_t
 201xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da)
 202{
 203        return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog));
 204}
 205
 206/*
 207 * Convert block (dablk) to byte offset in space
 208 */
 209static inline xfs_dir2_off_t
 210xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da)
 211{
 212        return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0);
 213}
 214
 215/*
 216 * Directory tail pointer accessor functions. Based on block geometry.
 217 */
 218static inline struct xfs_dir2_block_tail *
 219xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr)
 220{
 221        return ((struct xfs_dir2_block_tail *)
 222                ((char *)hdr + geo->blksize)) - 1;
 223}
 224
 225static inline struct xfs_dir2_leaf_tail *
 226xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
 227{
 228        return (struct xfs_dir2_leaf_tail *)
 229                ((char *)lp + geo->blksize -
 230                  sizeof(struct xfs_dir2_leaf_tail));
 231}
 232
 233/*
 234 * The Linux API doesn't pass down the total size of the buffer
 235 * we read into down to the filesystem.  With the filldir concept
 236 * it's not needed for correct information, but the XFS dir2 leaf
 237 * code wants an estimate of the buffer size to calculate it's
 238 * readahead window and size the buffers used for mapping to
 239 * physical blocks.
 240 *
 241 * Try to give it an estimate that's good enough, maybe at some
 242 * point we can change the ->readdir prototype to include the
 243 * buffer size.  For now we use the current glibc buffer size.
 244 * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE.
 245 */
 246#define XFS_READDIR_BUFSIZE     (32768)
 247
 248unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
 249unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo,
 250                struct xfs_dir2_data_hdr *hdr);
 251bool xfs_dir2_namecheck(const void *name, size_t length);
 252
 253#endif  /* __XFS_DIR2_H__ */
 254