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 xfs_failaddr_t xfs_dir3_leaf_header_check(struct xfs_buf *bp, xfs_ino_t owner); 105 xfs_failaddr_t xfs_dir3_data_header_check(struct xfs_buf *bp, xfs_ino_t owner); 106 xfs_failaddr_t xfs_dir3_block_header_check(struct xfs_buf *bp, xfs_ino_t owner); 107 108 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops; 109 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops; 110 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops; 111 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops; 112 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops; 113 114 /* 115 * Directory offset/block conversion functions. 116 * 117 * DB blocks here are logical directory block numbers, not filesystem blocks. 118 */ 119 120 /* 121 * Convert dataptr to byte in file space 122 */ 123 static inline xfs_dir2_off_t 124 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp) 125 { 126 return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG; 127 } 128 129 /* 130 * Convert byte in file space to dataptr. It had better be aligned. 131 */ 132 static inline xfs_dir2_dataptr_t 133 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by) 134 { 135 return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG); 136 } 137 138 /* 139 * Convert byte in space to (DB) block 140 */ 141 static inline xfs_dir2_db_t 142 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 143 { 144 return (xfs_dir2_db_t)(by >> geo->blklog); 145 } 146 147 /* 148 * Convert dataptr to a block number 149 */ 150 static inline xfs_dir2_db_t 151 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp) 152 { 153 return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp)); 154 } 155 156 /* 157 * Convert byte in space to offset in a block 158 */ 159 static inline xfs_dir2_data_aoff_t 160 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 161 { 162 return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1)); 163 } 164 165 /* 166 * Convert dataptr to a byte offset in a block 167 */ 168 static inline xfs_dir2_data_aoff_t 169 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp) 170 { 171 return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp)); 172 } 173 174 /* 175 * Convert block and offset to byte in space 176 */ 177 static inline xfs_dir2_off_t 178 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db, 179 xfs_dir2_data_aoff_t o) 180 { 181 return ((xfs_dir2_off_t)db << geo->blklog) + o; 182 } 183 184 /* 185 * Convert block (DB) to block (dablk) 186 */ 187 static inline xfs_dablk_t 188 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db) 189 { 190 return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog)); 191 } 192 193 /* 194 * Convert byte in space to (DA) block 195 */ 196 static inline xfs_dablk_t 197 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 198 { 199 return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by)); 200 } 201 202 /* 203 * Convert block and offset to dataptr 204 */ 205 static inline xfs_dir2_dataptr_t 206 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db, 207 xfs_dir2_data_aoff_t o) 208 { 209 return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o)); 210 } 211 212 /* 213 * Convert block (dablk) to block (DB) 214 */ 215 static inline xfs_dir2_db_t 216 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da) 217 { 218 return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog)); 219 } 220 221 /* 222 * Convert block (dablk) to byte offset in space 223 */ 224 static inline xfs_dir2_off_t 225 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da) 226 { 227 return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0); 228 } 229 230 /* 231 * Directory tail pointer accessor functions. Based on block geometry. 232 */ 233 static inline struct xfs_dir2_block_tail * 234 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr) 235 { 236 return ((struct xfs_dir2_block_tail *) 237 ((char *)hdr + geo->blksize)) - 1; 238 } 239 240 static inline struct xfs_dir2_leaf_tail * 241 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp) 242 { 243 return (struct xfs_dir2_leaf_tail *) 244 ((char *)lp + geo->blksize - 245 sizeof(struct xfs_dir2_leaf_tail)); 246 } 247 248 /* 249 * The Linux API doesn't pass down the total size of the buffer 250 * we read into down to the filesystem. With the filldir concept 251 * it's not needed for correct information, but the XFS dir2 leaf 252 * code wants an estimate of the buffer size to calculate it's 253 * readahead window and size the buffers used for mapping to 254 * physical blocks. 255 * 256 * Try to give it an estimate that's good enough, maybe at some 257 * point we can change the ->readdir prototype to include the 258 * buffer size. For now we use the current glibc buffer size. 259 * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE. 260 */ 261 #define XFS_READDIR_BUFSIZE (32768) 262 263 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype); 264 unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo, 265 struct xfs_dir2_data_hdr *hdr); 266 bool xfs_dir2_namecheck(const void *name, size_t length); 267 268 /* 269 * The "ascii-ci" feature was created to speed up case-insensitive lookups for 270 * a Samba product. Because of the inherent problems with CI and UTF-8 271 * encoding, etc, it was decided that Samba would be configured to export 272 * latin1/iso 8859-1 encodings as that covered >90% of the target markets for 273 * the product. Hence the "ascii-ci" casefolding code could be encoded into 274 * the XFS directory operations and remove all the overhead of casefolding from 275 * Samba. 276 * 277 * To provide consistent hashing behavior between the userspace and kernel, 278 * these functions prepare names for hashing by transforming specific bytes 279 * to other bytes. Robustness with other encodings is not guaranteed. 280 */ 281 static inline bool xfs_ascii_ci_need_xfrm(unsigned char c) 282 { 283 if (c >= 0x41 && c <= 0x5a) /* A-Z */ 284 return true; 285 if (c >= 0xc0 && c <= 0xd6) /* latin A-O with accents */ 286 return true; 287 if (c >= 0xd8 && c <= 0xde) /* latin O-Y with accents */ 288 return true; 289 return false; 290 } 291 292 static inline unsigned char xfs_ascii_ci_xfrm(unsigned char c) 293 { 294 if (xfs_ascii_ci_need_xfrm(c)) 295 c -= 'A' - 'a'; 296 return c; 297 } 298 299 #endif /* __XFS_DIR2_H__ */ 300