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 /* 40 * Convert inode mode to directory entry filetype 41 */ 42 extern unsigned char xfs_mode_to_ftype(int mode); 43 44 /* 45 * Generic directory interface routines 46 */ 47 extern void xfs_dir_startup(void); 48 extern int xfs_da_mount(struct xfs_mount *mp); 49 extern void xfs_da_unmount(struct xfs_mount *mp); 50 51 extern int xfs_dir_isempty(struct xfs_inode *dp); 52 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp, 53 struct xfs_inode *pdp); 54 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp, 55 const struct xfs_name *name, xfs_ino_t inum, 56 xfs_extlen_t tot); 57 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp, 58 const struct xfs_name *name, xfs_ino_t *inum, 59 struct xfs_name *ci_name); 60 extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp, 61 struct xfs_name *name, xfs_ino_t ino, 62 xfs_extlen_t tot); 63 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp, 64 const struct xfs_name *name, xfs_ino_t inum, 65 xfs_extlen_t tot); 66 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp, 67 struct xfs_name *name); 68 69 /* 70 * Direct call from the bmap code, bypassing the generic directory layer. 71 */ 72 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args); 73 74 /* 75 * Interface routines used by userspace utilities 76 */ 77 extern int xfs_dir2_isblock(struct xfs_da_args *args, bool *isblock); 78 extern int xfs_dir2_isleaf(struct xfs_da_args *args, bool *isleaf); 79 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db, 80 struct xfs_buf *bp); 81 82 extern void xfs_dir2_data_freescan(struct xfs_mount *mp, 83 struct xfs_dir2_data_hdr *hdr, int *loghead); 84 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args, 85 struct xfs_buf *bp, struct xfs_dir2_data_entry *dep); 86 extern void xfs_dir2_data_log_header(struct xfs_da_args *args, 87 struct xfs_buf *bp); 88 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args, 89 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup); 90 extern void xfs_dir2_data_make_free(struct xfs_da_args *args, 91 struct xfs_buf *bp, xfs_dir2_data_aoff_t offset, 92 xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp); 93 extern int xfs_dir2_data_use_free(struct xfs_da_args *args, 94 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup, 95 xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len, 96 int *needlogp, int *needscanp); 97 98 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind( 99 struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf, 100 struct xfs_dir2_data_unused *dup); 101 102 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino); 103 104 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops; 105 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops; 106 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops; 107 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops; 108 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops; 109 110 /* 111 * Directory offset/block conversion functions. 112 * 113 * DB blocks here are logical directory block numbers, not filesystem blocks. 114 */ 115 116 /* 117 * Convert dataptr to byte in file space 118 */ 119 static inline xfs_dir2_off_t 120 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp) 121 { 122 return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG; 123 } 124 125 /* 126 * Convert byte in file space to dataptr. It had better be aligned. 127 */ 128 static inline xfs_dir2_dataptr_t 129 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by) 130 { 131 return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG); 132 } 133 134 /* 135 * Convert byte in space to (DB) block 136 */ 137 static inline xfs_dir2_db_t 138 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 139 { 140 return (xfs_dir2_db_t)(by >> geo->blklog); 141 } 142 143 /* 144 * Convert dataptr to a block number 145 */ 146 static inline xfs_dir2_db_t 147 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp) 148 { 149 return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp)); 150 } 151 152 /* 153 * Convert byte in space to offset in a block 154 */ 155 static inline xfs_dir2_data_aoff_t 156 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 157 { 158 return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1)); 159 } 160 161 /* 162 * Convert dataptr to a byte offset in a block 163 */ 164 static inline xfs_dir2_data_aoff_t 165 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp) 166 { 167 return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp)); 168 } 169 170 /* 171 * Convert block and offset to byte in space 172 */ 173 static inline xfs_dir2_off_t 174 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db, 175 xfs_dir2_data_aoff_t o) 176 { 177 return ((xfs_dir2_off_t)db << geo->blklog) + o; 178 } 179 180 /* 181 * Convert block (DB) to block (dablk) 182 */ 183 static inline xfs_dablk_t 184 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db) 185 { 186 return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog)); 187 } 188 189 /* 190 * Convert byte in space to (DA) block 191 */ 192 static inline xfs_dablk_t 193 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 194 { 195 return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by)); 196 } 197 198 /* 199 * Convert block and offset to dataptr 200 */ 201 static inline xfs_dir2_dataptr_t 202 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db, 203 xfs_dir2_data_aoff_t o) 204 { 205 return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o)); 206 } 207 208 /* 209 * Convert block (dablk) to block (DB) 210 */ 211 static inline xfs_dir2_db_t 212 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da) 213 { 214 return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog)); 215 } 216 217 /* 218 * Convert block (dablk) to byte offset in space 219 */ 220 static inline xfs_dir2_off_t 221 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da) 222 { 223 return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0); 224 } 225 226 /* 227 * Directory tail pointer accessor functions. Based on block geometry. 228 */ 229 static inline struct xfs_dir2_block_tail * 230 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr) 231 { 232 return ((struct xfs_dir2_block_tail *) 233 ((char *)hdr + geo->blksize)) - 1; 234 } 235 236 static inline struct xfs_dir2_leaf_tail * 237 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp) 238 { 239 return (struct xfs_dir2_leaf_tail *) 240 ((char *)lp + geo->blksize - 241 sizeof(struct xfs_dir2_leaf_tail)); 242 } 243 244 /* 245 * The Linux API doesn't pass down the total size of the buffer 246 * we read into down to the filesystem. With the filldir concept 247 * it's not needed for correct information, but the XFS dir2 leaf 248 * code wants an estimate of the buffer size to calculate it's 249 * readahead window and size the buffers used for mapping to 250 * physical blocks. 251 * 252 * Try to give it an estimate that's good enough, maybe at some 253 * point we can change the ->readdir prototype to include the 254 * buffer size. For now we use the current glibc buffer size. 255 * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE. 256 */ 257 #define XFS_READDIR_BUFSIZE (32768) 258 259 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype); 260 unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo, 261 struct xfs_dir2_data_hdr *hdr); 262 bool xfs_dir2_namecheck(const void *name, size_t length); 263 264 /* 265 * The "ascii-ci" feature was created to speed up case-insensitive lookups for 266 * a Samba product. Because of the inherent problems with CI and UTF-8 267 * encoding, etc, it was decided that Samba would be configured to export 268 * latin1/iso 8859-1 encodings as that covered >90% of the target markets for 269 * the product. Hence the "ascii-ci" casefolding code could be encoded into 270 * the XFS directory operations and remove all the overhead of casefolding from 271 * Samba. 272 * 273 * To provide consistent hashing behavior between the userspace and kernel, 274 * these functions prepare names for hashing by transforming specific bytes 275 * to other bytes. Robustness with other encodings is not guaranteed. 276 */ 277 static inline bool xfs_ascii_ci_need_xfrm(unsigned char c) 278 { 279 if (c >= 0x41 && c <= 0x5a) /* A-Z */ 280 return true; 281 if (c >= 0xc0 && c <= 0xd6) /* latin A-O with accents */ 282 return true; 283 if (c >= 0xd8 && c <= 0xde) /* latin O-Y with accents */ 284 return true; 285 return false; 286 } 287 288 static inline unsigned char xfs_ascii_ci_xfrm(unsigned char c) 289 { 290 if (xfs_ascii_ci_need_xfrm(c)) 291 c -= 'A' - 'a'; 292 return c; 293 } 294 295 #endif /* __XFS_DIR2_H__ */ 296