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 26 /* 27 * Convert inode mode to directory entry filetype 28 */ 29 extern unsigned char xfs_mode_to_ftype(int mode); 30 31 /* 32 * Generic directory interface routines 33 */ 34 extern void xfs_dir_startup(void); 35 extern int xfs_da_mount(struct xfs_mount *mp); 36 extern void xfs_da_unmount(struct xfs_mount *mp); 37 38 extern int xfs_dir_isempty(struct xfs_inode *dp); 39 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp, 40 struct xfs_inode *pdp); 41 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp, 42 const struct xfs_name *name, xfs_ino_t inum, 43 xfs_extlen_t tot); 44 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp, 45 const struct xfs_name *name, xfs_ino_t *inum, 46 struct xfs_name *ci_name); 47 extern 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); 50 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp, 51 const struct xfs_name *name, xfs_ino_t inum, 52 xfs_extlen_t tot); 53 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp, 54 struct xfs_name *name); 55 56 /* 57 * Direct call from the bmap code, bypassing the generic directory layer. 58 */ 59 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args); 60 61 /* 62 * Interface routines used by userspace utilities 63 */ 64 extern int xfs_dir2_isblock(struct xfs_da_args *args, bool *isblock); 65 extern int xfs_dir2_isleaf(struct xfs_da_args *args, bool *isleaf); 66 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db, 67 struct xfs_buf *bp); 68 69 extern void xfs_dir2_data_freescan(struct xfs_mount *mp, 70 struct xfs_dir2_data_hdr *hdr, int *loghead); 71 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args, 72 struct xfs_buf *bp, struct xfs_dir2_data_entry *dep); 73 extern void xfs_dir2_data_log_header(struct xfs_da_args *args, 74 struct xfs_buf *bp); 75 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args, 76 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup); 77 extern void xfs_dir2_data_make_free(struct xfs_da_args *args, 78 struct xfs_buf *bp, xfs_dir2_data_aoff_t offset, 79 xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp); 80 extern int xfs_dir2_data_use_free(struct xfs_da_args *args, 81 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup, 82 xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len, 83 int *needlogp, int *needscanp); 84 85 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind( 86 struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf, 87 struct xfs_dir2_data_unused *dup); 88 89 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino); 90 91 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops; 92 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops; 93 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops; 94 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops; 95 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops; 96 97 /* 98 * Directory offset/block conversion functions. 99 * 100 * DB blocks here are logical directory block numbers, not filesystem blocks. 101 */ 102 103 /* 104 * Convert dataptr to byte in file space 105 */ 106 static inline xfs_dir2_off_t 107 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp) 108 { 109 return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG; 110 } 111 112 /* 113 * Convert byte in file space to dataptr. It had better be aligned. 114 */ 115 static inline xfs_dir2_dataptr_t 116 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by) 117 { 118 return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG); 119 } 120 121 /* 122 * Convert byte in space to (DB) block 123 */ 124 static inline xfs_dir2_db_t 125 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 126 { 127 return (xfs_dir2_db_t)(by >> geo->blklog); 128 } 129 130 /* 131 * Convert dataptr to a block number 132 */ 133 static inline xfs_dir2_db_t 134 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp) 135 { 136 return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp)); 137 } 138 139 /* 140 * Convert byte in space to offset in a block 141 */ 142 static inline xfs_dir2_data_aoff_t 143 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 144 { 145 return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1)); 146 } 147 148 /* 149 * Convert dataptr to a byte offset in a block 150 */ 151 static inline xfs_dir2_data_aoff_t 152 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp) 153 { 154 return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp)); 155 } 156 157 /* 158 * Convert block and offset to byte in space 159 */ 160 static inline xfs_dir2_off_t 161 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db, 162 xfs_dir2_data_aoff_t o) 163 { 164 return ((xfs_dir2_off_t)db << geo->blklog) + o; 165 } 166 167 /* 168 * Convert block (DB) to block (dablk) 169 */ 170 static inline xfs_dablk_t 171 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db) 172 { 173 return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog)); 174 } 175 176 /* 177 * Convert byte in space to (DA) block 178 */ 179 static inline xfs_dablk_t 180 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by) 181 { 182 return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by)); 183 } 184 185 /* 186 * Convert block and offset to dataptr 187 */ 188 static inline xfs_dir2_dataptr_t 189 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db, 190 xfs_dir2_data_aoff_t o) 191 { 192 return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o)); 193 } 194 195 /* 196 * Convert block (dablk) to block (DB) 197 */ 198 static inline xfs_dir2_db_t 199 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da) 200 { 201 return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog)); 202 } 203 204 /* 205 * Convert block (dablk) to byte offset in space 206 */ 207 static inline xfs_dir2_off_t 208 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da) 209 { 210 return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0); 211 } 212 213 /* 214 * Directory tail pointer accessor functions. Based on block geometry. 215 */ 216 static inline struct xfs_dir2_block_tail * 217 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr) 218 { 219 return ((struct xfs_dir2_block_tail *) 220 ((char *)hdr + geo->blksize)) - 1; 221 } 222 223 static inline struct xfs_dir2_leaf_tail * 224 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp) 225 { 226 return (struct xfs_dir2_leaf_tail *) 227 ((char *)lp + geo->blksize - 228 sizeof(struct xfs_dir2_leaf_tail)); 229 } 230 231 /* 232 * The Linux API doesn't pass down the total size of the buffer 233 * we read into down to the filesystem. With the filldir concept 234 * it's not needed for correct information, but the XFS dir2 leaf 235 * code wants an estimate of the buffer size to calculate it's 236 * readahead window and size the buffers used for mapping to 237 * physical blocks. 238 * 239 * Try to give it an estimate that's good enough, maybe at some 240 * point we can change the ->readdir prototype to include the 241 * buffer size. For now we use the current glibc buffer size. 242 * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE. 243 */ 244 #define XFS_READDIR_BUFSIZE (32768) 245 246 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype); 247 unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo, 248 struct xfs_dir2_data_hdr *hdr); 249 bool xfs_dir2_namecheck(const void *name, size_t length); 250 251 /* 252 * The "ascii-ci" feature was created to speed up case-insensitive lookups for 253 * a Samba product. Because of the inherent problems with CI and UTF-8 254 * encoding, etc, it was decided that Samba would be configured to export 255 * latin1/iso 8859-1 encodings as that covered >90% of the target markets for 256 * the product. Hence the "ascii-ci" casefolding code could be encoded into 257 * the XFS directory operations and remove all the overhead of casefolding from 258 * Samba. 259 * 260 * To provide consistent hashing behavior between the userspace and kernel, 261 * these functions prepare names for hashing by transforming specific bytes 262 * to other bytes. Robustness with other encodings is not guaranteed. 263 */ 264 static inline bool xfs_ascii_ci_need_xfrm(unsigned char c) 265 { 266 if (c >= 0x41 && c <= 0x5a) /* A-Z */ 267 return true; 268 if (c >= 0xc0 && c <= 0xd6) /* latin A-O with accents */ 269 return true; 270 if (c >= 0xd8 && c <= 0xde) /* latin O-Y with accents */ 271 return true; 272 return false; 273 } 274 275 static inline unsigned char xfs_ascii_ci_xfrm(unsigned char c) 276 { 277 if (xfs_ascii_ci_need_xfrm(c)) 278 c -= 'A' - 'a'; 279 return c; 280 } 281 282 #endif /* __XFS_DIR2_H__ */ 283