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_da_args; 13 struct xfs_inode; 14 struct xfs_mount; 15 struct xfs_trans; 16 struct xfs_dir2_sf_hdr; 17 struct xfs_dir2_sf_entry; 18 struct xfs_dir2_data_hdr; 19 struct xfs_dir2_data_entry; 20 struct xfs_dir2_data_unused; 21 struct xfs_dir3_icfree_hdr; 22 struct xfs_dir3_icleaf_hdr; 23 24 extern const struct xfs_name xfs_name_dotdot; 25 extern const struct xfs_name xfs_name_dot; 26 27 static inline bool 28 xfs_dir2_samename( 29 const struct xfs_name *n1, 30 const struct xfs_name *n2) 31 { 32 if (n1 == n2) 33 return true; 34 if (n1->len != n2->len) 35 return false; 36 return !memcmp(n1->name, n2->name, n1->len); 37 } 38 39 enum xfs_dir2_fmt { 40 XFS_DIR2_FMT_SF, 41 XFS_DIR2_FMT_BLOCK, 42 XFS_DIR2_FMT_LEAF, 43 XFS_DIR2_FMT_NODE, 44 XFS_DIR2_FMT_ERROR, 45 }; 46 47 enum xfs_dir2_fmt xfs_dir2_format(struct xfs_da_args *args, int *error); 48 49 /* 50 * Convert inode mode to directory entry filetype 51 */ 52 extern unsigned char xfs_mode_to_ftype(int mode); 53 54 /* 55 * Generic directory interface routines 56 */ 57 extern void xfs_dir_startup(void); 58 extern int xfs_da_mount(struct xfs_mount *mp); 59 extern void xfs_da_unmount(struct xfs_mount *mp); 60 61 extern int xfs_dir_isempty(struct xfs_inode *dp); 62 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp, 63 struct xfs_inode *pdp); 64 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp, 65 const struct xfs_name *name, xfs_ino_t inum, 66 xfs_extlen_t tot); 67 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp, 68 const struct xfs_name *name, xfs_ino_t *inum, 69 struct xfs_name *ci_name); 70 extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp, 71 const struct xfs_name *name, xfs_ino_t ino, 72 xfs_extlen_t tot); 73 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp, 74 const struct xfs_name *name, xfs_ino_t inum, 75 xfs_extlen_t tot); 76 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp, 77 struct xfs_name *name); 78 79 int xfs_dir_lookup_args(struct xfs_da_args *args); 80 int xfs_dir_createname_args(struct xfs_da_args *args); 81 int xfs_dir_removename_args(struct xfs_da_args *args); 82 int xfs_dir_replace_args(struct xfs_da_args *args); 83 84 /* 85 * Direct call from the bmap code, bypassing the generic directory layer. 86 */ 87 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args); 88 89 /* 90 * Interface routines used by userspace utilities 91 */ 92 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db, 93 struct xfs_buf *bp); 94 95 extern void xfs_dir2_data_freescan(struct xfs_mount *mp, 96 struct xfs_dir2_data_hdr *hdr, int *loghead); 97 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args, 98 struct xfs_buf *bp, struct xfs_dir2_data_entry *dep); 99 extern void xfs_dir2_data_log_header(struct xfs_da_args *args, 100 struct xfs_buf *bp); 101 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args, 102 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup); 103 extern void xfs_dir2_data_make_free(struct xfs_da_args *args, 104 struct xfs_buf *bp, xfs_dir2_data_aoff_t offset, 105 xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp); 106 extern int xfs_dir2_data_use_free(struct xfs_da_args *args, 107 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup, 108 xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len, 109 int *needlogp, int *needscanp); 110 111 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind( 112 struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf, 113 struct xfs_dir2_data_unused *dup); 114 115 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino); 116 117 xfs_failaddr_t xfs_dir3_leaf_header_check(struct xfs_buf *bp, xfs_ino_t owner); 118 xfs_failaddr_t xfs_dir3_data_header_check(struct xfs_buf *bp, xfs_ino_t owner); 119 xfs_failaddr_t xfs_dir3_block_header_check(struct xfs_buf *bp, xfs_ino_t owner); 120 121 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops; 122 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops; 123 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops; 124 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops; 125 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops; 126 127 /* 128 * Directory offset/block conversion functions. 129 * 130 * DB blocks here are logical directory block numbers, not filesystem blocks. 131 */ 132 133 /* 134 * Convert dataptr to byte in file space 135 */ 136 static inline xfs_dir2_off_t 137 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp) 138 { 139 return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG; 140 } 141 142 /* 143 * Convert byte in file space to dataptr. It had better be aligned. 144 */ 145 static inline xfs_dir2_dataptr_t 146 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by) 147 { 148 return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG); 149 } 150 151 /* 152 * Convert byte in space to (DB) block 153 */ 154 static inline xfs_dir2_db_t 155 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 156 { 157 return (xfs_dir2_db_t)(by >> geo->blklog); 158 } 159 160 /* 161 * Convert dataptr to a block number 162 */ 163 static inline xfs_dir2_db_t 164 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp) 165 { 166 return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp)); 167 } 168 169 /* 170 * Convert byte in space to offset in a block 171 */ 172 static inline xfs_dir2_data_aoff_t 173 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 174 { 175 return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1)); 176 } 177 178 /* 179 * Convert dataptr to a byte offset in a block 180 */ 181 static inline xfs_dir2_data_aoff_t 182 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp) 183 { 184 return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp)); 185 } 186 187 /* 188 * Convert block and offset to byte in space 189 */ 190 static inline xfs_dir2_off_t 191 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db, 192 xfs_dir2_data_aoff_t o) 193 { 194 return ((xfs_dir2_off_t)db << geo->blklog) + o; 195 } 196 197 /* 198 * Convert block (DB) to block (dablk) 199 */ 200 static inline xfs_dablk_t 201 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db) 202 { 203 return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog)); 204 } 205 206 /* 207 * Convert byte in space to (DA) block 208 */ 209 static inline xfs_dablk_t 210 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 211 { 212 return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by)); 213 } 214 215 /* 216 * Convert block and offset to dataptr 217 */ 218 static inline xfs_dir2_dataptr_t 219 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db, 220 xfs_dir2_data_aoff_t o) 221 { 222 return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o)); 223 } 224 225 /* 226 * Convert block (dablk) to block (DB) 227 */ 228 static inline xfs_dir2_db_t 229 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da) 230 { 231 return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog)); 232 } 233 234 /* 235 * Convert block (dablk) to byte offset in space 236 */ 237 static inline xfs_dir2_off_t 238 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da) 239 { 240 return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0); 241 } 242 243 /* 244 * Directory tail pointer accessor functions. Based on block geometry. 245 */ 246 static inline struct xfs_dir2_block_tail * 247 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr) 248 { 249 return ((struct xfs_dir2_block_tail *) 250 ((char *)hdr + geo->blksize)) - 1; 251 } 252 253 static inline struct xfs_dir2_leaf_tail * 254 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp) 255 { 256 return (struct xfs_dir2_leaf_tail *) 257 ((char *)lp + geo->blksize - 258 sizeof(struct xfs_dir2_leaf_tail)); 259 } 260 261 /* 262 * The Linux API doesn't pass down the total size of the buffer 263 * we read into down to the filesystem. With the filldir concept 264 * it's not needed for correct information, but the XFS dir2 leaf 265 * code wants an estimate of the buffer size to calculate it's 266 * readahead window and size the buffers used for mapping to 267 * physical blocks. 268 * 269 * Try to give it an estimate that's good enough, maybe at some 270 * point we can change the ->readdir prototype to include the 271 * buffer size. For now we use the current glibc buffer size. 272 * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE. 273 */ 274 #define XFS_READDIR_BUFSIZE (32768) 275 276 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype); 277 unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo, 278 struct xfs_dir2_data_hdr *hdr); 279 bool xfs_dir2_namecheck(const void *name, size_t length); 280 281 /* 282 * The "ascii-ci" feature was created to speed up case-insensitive lookups for 283 * a Samba product. Because of the inherent problems with CI and UTF-8 284 * encoding, etc, it was decided that Samba would be configured to export 285 * latin1/iso 8859-1 encodings as that covered >90% of the target markets for 286 * the product. Hence the "ascii-ci" casefolding code could be encoded into 287 * the XFS directory operations and remove all the overhead of casefolding from 288 * Samba. 289 * 290 * To provide consistent hashing behavior between the userspace and kernel, 291 * these functions prepare names for hashing by transforming specific bytes 292 * to other bytes. Robustness with other encodings is not guaranteed. 293 */ 294 static inline bool xfs_ascii_ci_need_xfrm(unsigned char c) 295 { 296 if (c >= 0x41 && c <= 0x5a) /* A-Z */ 297 return true; 298 if (c >= 0xc0 && c <= 0xd6) /* latin A-O with accents */ 299 return true; 300 if (c >= 0xd8 && c <= 0xde) /* latin O-Y with accents */ 301 return true; 302 return false; 303 } 304 305 static inline unsigned char xfs_ascii_ci_xfrm(unsigned char c) 306 { 307 if (xfs_ascii_ci_need_xfrm(c)) 308 c -= 'A' - 'a'; 309 return c; 310 } 311 312 #endif /* __XFS_DIR2_H__ */ 313