Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc. |
Dave Chinner | f5f3d9b | 2013-04-03 16:11:20 +1100 | [diff] [blame] | 3 | * Copyright (c) 2013 Red Hat, Inc. |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 4 | * All Rights Reserved. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License as |
| 8 | * published by the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it would be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program; if not, write the Free Software Foundation, |
| 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | */ |
Dave Chinner | 5706278 | 2013-10-15 09:17:51 +1100 | [diff] [blame] | 19 | #ifndef __XFS_DA_FORMAT_H__ |
| 20 | #define __XFS_DA_FORMAT_H__ |
| 21 | |
| 22 | /*======================================================================== |
| 23 | * Directory Structure when greater than XFS_LBSIZE(mp) bytes. |
| 24 | *========================================================================*/ |
| 25 | |
| 26 | /* |
| 27 | * This structure is common to both leaf nodes and non-leaf nodes in the Btree. |
| 28 | * |
| 29 | * It is used to manage a doubly linked list of all blocks at the same |
| 30 | * level in the Btree, and to identify which type of block this is. |
| 31 | */ |
| 32 | #define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */ |
| 33 | #define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */ |
| 34 | #define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */ |
| 35 | #define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */ |
| 36 | |
| 37 | typedef struct xfs_da_blkinfo { |
| 38 | __be32 forw; /* previous block in list */ |
| 39 | __be32 back; /* following block in list */ |
| 40 | __be16 magic; /* validity check on block */ |
| 41 | __be16 pad; /* unused */ |
| 42 | } xfs_da_blkinfo_t; |
| 43 | |
| 44 | /* |
| 45 | * CRC enabled directory structure types |
| 46 | * |
| 47 | * The headers change size for the additional verification information, but |
| 48 | * otherwise the tree layouts and contents are unchanged. Hence the da btree |
| 49 | * code can use the struct xfs_da_blkinfo for manipulating the tree links and |
| 50 | * magic numbers without modification for both v2 and v3 nodes. |
| 51 | */ |
| 52 | #define XFS_DA3_NODE_MAGIC 0x3ebe /* magic number: non-leaf blocks */ |
| 53 | #define XFS_ATTR3_LEAF_MAGIC 0x3bee /* magic number: attribute leaf blks */ |
| 54 | #define XFS_DIR3_LEAF1_MAGIC 0x3df1 /* magic number: v2 dirlf single blks */ |
| 55 | #define XFS_DIR3_LEAFN_MAGIC 0x3dff /* magic number: v2 dirlf multi blks */ |
| 56 | |
| 57 | struct xfs_da3_blkinfo { |
| 58 | /* |
| 59 | * the node link manipulation code relies on the fact that the first |
| 60 | * element of this structure is the struct xfs_da_blkinfo so it can |
| 61 | * ignore the differences in the rest of the structures. |
| 62 | */ |
| 63 | struct xfs_da_blkinfo hdr; |
| 64 | __be32 crc; /* CRC of block */ |
| 65 | __be64 blkno; /* first block of the buffer */ |
| 66 | __be64 lsn; /* sequence number of last write */ |
| 67 | uuid_t uuid; /* filesystem we belong to */ |
| 68 | __be64 owner; /* inode that owns the block */ |
| 69 | }; |
| 70 | |
| 71 | /* |
| 72 | * This is the structure of the root and intermediate nodes in the Btree. |
| 73 | * The leaf nodes are defined above. |
| 74 | * |
| 75 | * Entries are not packed. |
| 76 | * |
| 77 | * Since we have duplicate keys, use a binary search but always follow |
| 78 | * all match in the block, not just the first match found. |
| 79 | */ |
| 80 | #define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */ |
| 81 | |
| 82 | typedef struct xfs_da_node_hdr { |
| 83 | struct xfs_da_blkinfo info; /* block type, links, etc. */ |
| 84 | __be16 __count; /* count of active entries */ |
| 85 | __be16 __level; /* level above leaves (leaf == 0) */ |
| 86 | } xfs_da_node_hdr_t; |
| 87 | |
| 88 | struct xfs_da3_node_hdr { |
| 89 | struct xfs_da3_blkinfo info; /* block type, links, etc. */ |
| 90 | __be16 __count; /* count of active entries */ |
| 91 | __be16 __level; /* level above leaves (leaf == 0) */ |
| 92 | __be32 __pad32; |
| 93 | }; |
| 94 | |
| 95 | #define XFS_DA3_NODE_CRC_OFF (offsetof(struct xfs_da3_node_hdr, info.crc)) |
| 96 | |
| 97 | typedef struct xfs_da_node_entry { |
| 98 | __be32 hashval; /* hash value for this descendant */ |
| 99 | __be32 before; /* Btree block before this key */ |
| 100 | } xfs_da_node_entry_t; |
| 101 | |
| 102 | typedef struct xfs_da_intnode { |
| 103 | struct xfs_da_node_hdr hdr; |
| 104 | struct xfs_da_node_entry __btree[]; |
| 105 | } xfs_da_intnode_t; |
| 106 | |
| 107 | struct xfs_da3_intnode { |
| 108 | struct xfs_da3_node_hdr hdr; |
| 109 | struct xfs_da_node_entry __btree[]; |
| 110 | }; |
| 111 | |
| 112 | /* |
| 113 | * In-core version of the node header to abstract the differences in the v2 and |
| 114 | * v3 disk format of the headers. Callers need to convert to/from disk format as |
| 115 | * appropriate. |
| 116 | */ |
| 117 | struct xfs_da3_icnode_hdr { |
| 118 | __uint32_t forw; |
| 119 | __uint32_t back; |
| 120 | __uint16_t magic; |
| 121 | __uint16_t count; |
| 122 | __uint16_t level; |
| 123 | }; |
| 124 | |
Dave Chinner | 5706278 | 2013-10-15 09:17:51 +1100 | [diff] [blame] | 125 | #define XFS_LBSIZE(mp) (mp)->m_sb.sb_blocksize |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 126 | |
| 127 | /* |
| 128 | * Directory version 2. |
| 129 | * |
| 130 | * There are 4 possible formats: |
| 131 | * - shortform - embedded into the inode |
| 132 | * - single block - data with embedded leaf at the end |
| 133 | * - multiple data blocks, single leaf+freeindex block |
| 134 | * - data blocks, node and leaf blocks (btree), freeindex blocks |
| 135 | * |
| 136 | * Note: many node blocks structures and constants are shared with the attr |
| 137 | * code and defined in xfs_da_btree.h. |
| 138 | */ |
| 139 | |
| 140 | #define XFS_DIR2_BLOCK_MAGIC 0x58443242 /* XD2B: single block dirs */ |
| 141 | #define XFS_DIR2_DATA_MAGIC 0x58443244 /* XD2D: multiblock dirs */ |
| 142 | #define XFS_DIR2_FREE_MAGIC 0x58443246 /* XD2F: free index blocks */ |
| 143 | |
| 144 | /* |
Dave Chinner | f5f3d9b | 2013-04-03 16:11:20 +1100 | [diff] [blame] | 145 | * Directory Version 3 With CRCs. |
| 146 | * |
| 147 | * The tree formats are the same as for version 2 directories. The difference |
| 148 | * is in the block header and dirent formats. In many cases the v3 structures |
| 149 | * use v2 definitions as they are no different and this makes code sharing much |
| 150 | * easier. |
| 151 | * |
| 152 | * Also, the xfs_dir3_*() functions handle both v2 and v3 formats - if the |
| 153 | * format is v2 then they switch to the existing v2 code, or the format is v3 |
| 154 | * they implement the v3 functionality. This means the existing dir2 is a mix of |
| 155 | * xfs_dir2/xfs_dir3 calls and functions. The xfs_dir3 functions are called |
| 156 | * where there is a difference in the formats, otherwise the code is unchanged. |
| 157 | * |
| 158 | * Where it is possible, the code decides what to do based on the magic numbers |
| 159 | * in the blocks rather than feature bits in the superblock. This means the code |
| 160 | * is as independent of the external XFS code as possible as doesn't require |
| 161 | * passing struct xfs_mount pointers into places where it isn't really |
| 162 | * necessary. |
| 163 | * |
| 164 | * Version 3 includes: |
| 165 | * |
| 166 | * - a larger block header for CRC and identification purposes and so the |
| 167 | * offsets of all the structures inside the blocks are different. |
| 168 | * |
| 169 | * - new magic numbers to be able to detect the v2/v3 types on the fly. |
| 170 | */ |
| 171 | |
| 172 | #define XFS_DIR3_BLOCK_MAGIC 0x58444233 /* XDB3: single block dirs */ |
| 173 | #define XFS_DIR3_DATA_MAGIC 0x58444433 /* XDD3: multiblock dirs */ |
Dave Chinner | cbc8adf | 2013-04-03 16:11:21 +1100 | [diff] [blame] | 174 | #define XFS_DIR3_FREE_MAGIC 0x58444633 /* XDF3: free index blocks */ |
Dave Chinner | f5f3d9b | 2013-04-03 16:11:20 +1100 | [diff] [blame] | 175 | |
| 176 | /* |
Dave Chinner | 0cb9776 | 2013-08-12 20:50:09 +1000 | [diff] [blame] | 177 | * Dirents in version 3 directories have a file type field. Additions to this |
| 178 | * list are an on-disk format change, requiring feature bits. Valid values |
| 179 | * are as follows: |
| 180 | */ |
| 181 | #define XFS_DIR3_FT_UNKNOWN 0 |
| 182 | #define XFS_DIR3_FT_REG_FILE 1 |
| 183 | #define XFS_DIR3_FT_DIR 2 |
| 184 | #define XFS_DIR3_FT_CHRDEV 3 |
| 185 | #define XFS_DIR3_FT_BLKDEV 4 |
| 186 | #define XFS_DIR3_FT_FIFO 5 |
| 187 | #define XFS_DIR3_FT_SOCK 6 |
| 188 | #define XFS_DIR3_FT_SYMLINK 7 |
| 189 | #define XFS_DIR3_FT_WHT 8 |
| 190 | |
| 191 | #define XFS_DIR3_FT_MAX 9 |
| 192 | |
| 193 | /* |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 194 | * Byte offset in data block and shortform entry. |
| 195 | */ |
| 196 | typedef __uint16_t xfs_dir2_data_off_t; |
| 197 | #define NULLDATAOFF 0xffffU |
| 198 | typedef uint xfs_dir2_data_aoff_t; /* argument form */ |
| 199 | |
| 200 | /* |
| 201 | * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t. |
| 202 | * Only need 16 bits, this is the byte offset into the single block form. |
| 203 | */ |
| 204 | typedef struct { __uint8_t i[2]; } __arch_pack xfs_dir2_sf_off_t; |
| 205 | |
| 206 | /* |
| 207 | * Offset in data space of a data entry. |
| 208 | */ |
| 209 | typedef __uint32_t xfs_dir2_dataptr_t; |
| 210 | #define XFS_DIR2_MAX_DATAPTR ((xfs_dir2_dataptr_t)0xffffffff) |
| 211 | #define XFS_DIR2_NULL_DATAPTR ((xfs_dir2_dataptr_t)0) |
| 212 | |
| 213 | /* |
| 214 | * Byte offset in a directory. |
| 215 | */ |
| 216 | typedef xfs_off_t xfs_dir2_off_t; |
| 217 | |
| 218 | /* |
| 219 | * Directory block number (logical dirblk in file) |
| 220 | */ |
| 221 | typedef __uint32_t xfs_dir2_db_t; |
| 222 | |
| 223 | /* |
| 224 | * Inode number stored as 8 8-bit values. |
| 225 | */ |
| 226 | typedef struct { __uint8_t i[8]; } xfs_dir2_ino8_t; |
| 227 | |
| 228 | /* |
| 229 | * Inode number stored as 4 8-bit values. |
| 230 | * Works a lot of the time, when all the inode numbers in a directory |
| 231 | * fit in 32 bits. |
| 232 | */ |
| 233 | typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t; |
| 234 | |
| 235 | typedef union { |
| 236 | xfs_dir2_ino8_t i8; |
| 237 | xfs_dir2_ino4_t i4; |
| 238 | } xfs_dir2_inou_t; |
| 239 | #define XFS_DIR2_MAX_SHORT_INUM ((xfs_ino_t)0xffffffffULL) |
| 240 | |
| 241 | /* |
| 242 | * Directory layout when stored internal to an inode. |
| 243 | * |
| 244 | * Small directories are packed as tightly as possible so as to fit into the |
| 245 | * literal area of the inode. These "shortform" directories consist of a |
| 246 | * single xfs_dir2_sf_hdr header followed by zero or more xfs_dir2_sf_entry |
| 247 | * structures. Due the different inode number storage size and the variable |
| 248 | * length name field in the xfs_dir2_sf_entry all these structure are |
| 249 | * variable length, and the accessors in this file should be used to iterate |
| 250 | * over them. |
| 251 | */ |
| 252 | typedef struct xfs_dir2_sf_hdr { |
| 253 | __uint8_t count; /* count of entries */ |
| 254 | __uint8_t i8count; /* count of 8-byte inode #s */ |
| 255 | xfs_dir2_inou_t parent; /* parent dir inode number */ |
| 256 | } __arch_pack xfs_dir2_sf_hdr_t; |
| 257 | |
| 258 | typedef struct xfs_dir2_sf_entry { |
| 259 | __u8 namelen; /* actual name length */ |
| 260 | xfs_dir2_sf_off_t offset; /* saved offset */ |
| 261 | __u8 name[]; /* name, variable size */ |
| 262 | /* |
Dave Chinner | 0cb9776 | 2013-08-12 20:50:09 +1000 | [diff] [blame] | 263 | * A single byte containing the file type field follows the inode |
| 264 | * number for version 3 directory entries. |
| 265 | * |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 266 | * A xfs_dir2_ino8_t or xfs_dir2_ino4_t follows here, at a |
| 267 | * variable offset after the name. |
| 268 | */ |
| 269 | } __arch_pack xfs_dir2_sf_entry_t; |
| 270 | |
| 271 | static inline int xfs_dir2_sf_hdr_size(int i8count) |
| 272 | { |
| 273 | return sizeof(struct xfs_dir2_sf_hdr) - |
| 274 | (i8count == 0) * |
| 275 | (sizeof(xfs_dir2_ino8_t) - sizeof(xfs_dir2_ino4_t)); |
| 276 | } |
| 277 | |
| 278 | static inline xfs_dir2_data_aoff_t |
| 279 | xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep) |
| 280 | { |
| 281 | return get_unaligned_be16(&sfep->offset.i); |
| 282 | } |
| 283 | |
| 284 | static inline void |
| 285 | xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off) |
| 286 | { |
| 287 | put_unaligned_be16(off, &sfep->offset.i); |
| 288 | } |
| 289 | |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 290 | static inline struct xfs_dir2_sf_entry * |
| 291 | xfs_dir2_sf_firstentry(struct xfs_dir2_sf_hdr *hdr) |
| 292 | { |
| 293 | return (struct xfs_dir2_sf_entry *) |
| 294 | ((char *)hdr + xfs_dir2_sf_hdr_size(hdr->i8count)); |
| 295 | } |
| 296 | |
Dave Chinner | 0cb9776 | 2013-08-12 20:50:09 +1000 | [diff] [blame] | 297 | /* |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 298 | * Data block structures. |
| 299 | * |
| 300 | * A pure data block looks like the following drawing on disk: |
| 301 | * |
| 302 | * +-------------------------------------------------+ |
| 303 | * | xfs_dir2_data_hdr_t | |
| 304 | * +-------------------------------------------------+ |
| 305 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| 306 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| 307 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| 308 | * | ... | |
| 309 | * +-------------------------------------------------+ |
| 310 | * | unused space | |
| 311 | * +-------------------------------------------------+ |
| 312 | * |
| 313 | * As all the entries are variable size structures the accessors below should |
| 314 | * be used to iterate over them. |
| 315 | * |
| 316 | * In addition to the pure data blocks for the data and node formats, |
| 317 | * most structures are also used for the combined data/freespace "block" |
| 318 | * format below. |
| 319 | */ |
| 320 | |
| 321 | #define XFS_DIR2_DATA_ALIGN_LOG 3 /* i.e., 8 bytes */ |
| 322 | #define XFS_DIR2_DATA_ALIGN (1 << XFS_DIR2_DATA_ALIGN_LOG) |
| 323 | #define XFS_DIR2_DATA_FREE_TAG 0xffff |
| 324 | #define XFS_DIR2_DATA_FD_COUNT 3 |
| 325 | |
| 326 | /* |
| 327 | * Directory address space divided into sections, |
| 328 | * spaces separated by 32GB. |
| 329 | */ |
| 330 | #define XFS_DIR2_SPACE_SIZE (1ULL << (32 + XFS_DIR2_DATA_ALIGN_LOG)) |
| 331 | #define XFS_DIR2_DATA_SPACE 0 |
| 332 | #define XFS_DIR2_DATA_OFFSET (XFS_DIR2_DATA_SPACE * XFS_DIR2_SPACE_SIZE) |
| 333 | #define XFS_DIR2_DATA_FIRSTDB(mp) \ |
| 334 | xfs_dir2_byte_to_db(mp, XFS_DIR2_DATA_OFFSET) |
| 335 | |
| 336 | /* |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 337 | * Describe a free area in the data block. |
| 338 | * |
| 339 | * The freespace will be formatted as a xfs_dir2_data_unused_t. |
| 340 | */ |
| 341 | typedef struct xfs_dir2_data_free { |
| 342 | __be16 offset; /* start of freespace */ |
| 343 | __be16 length; /* length of freespace */ |
| 344 | } xfs_dir2_data_free_t; |
| 345 | |
| 346 | /* |
| 347 | * Header for the data blocks. |
| 348 | * |
| 349 | * The code knows that XFS_DIR2_DATA_FD_COUNT is 3. |
| 350 | */ |
| 351 | typedef struct xfs_dir2_data_hdr { |
| 352 | __be32 magic; /* XFS_DIR2_DATA_MAGIC or */ |
| 353 | /* XFS_DIR2_BLOCK_MAGIC */ |
| 354 | xfs_dir2_data_free_t bestfree[XFS_DIR2_DATA_FD_COUNT]; |
| 355 | } xfs_dir2_data_hdr_t; |
| 356 | |
| 357 | /* |
Dave Chinner | f5f3d9b | 2013-04-03 16:11:20 +1100 | [diff] [blame] | 358 | * define a structure for all the verification fields we are adding to the |
| 359 | * directory block structures. This will be used in several structures. |
| 360 | * The magic number must be the first entry to align with all the dir2 |
| 361 | * structures so we determine how to decode them just by the magic number. |
| 362 | */ |
| 363 | struct xfs_dir3_blk_hdr { |
| 364 | __be32 magic; /* magic number */ |
| 365 | __be32 crc; /* CRC of block */ |
| 366 | __be64 blkno; /* first block of the buffer */ |
| 367 | __be64 lsn; /* sequence number of last write */ |
| 368 | uuid_t uuid; /* filesystem we belong to */ |
| 369 | __be64 owner; /* inode that owns the block */ |
| 370 | }; |
| 371 | |
| 372 | struct xfs_dir3_data_hdr { |
| 373 | struct xfs_dir3_blk_hdr hdr; |
| 374 | xfs_dir2_data_free_t best_free[XFS_DIR2_DATA_FD_COUNT]; |
Dave Chinner | 5170711 | 2013-06-12 12:19:07 +1000 | [diff] [blame] | 375 | __be32 pad; /* 64 bit alignment */ |
Dave Chinner | f5f3d9b | 2013-04-03 16:11:20 +1100 | [diff] [blame] | 376 | }; |
| 377 | |
| 378 | #define XFS_DIR3_DATA_CRC_OFF offsetof(struct xfs_dir3_data_hdr, hdr.crc) |
| 379 | |
Dave Chinner | f5f3d9b | 2013-04-03 16:11:20 +1100 | [diff] [blame] | 380 | /* |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 381 | * Active entry in a data block. |
| 382 | * |
| 383 | * Aligned to 8 bytes. After the variable length name field there is a |
Dave Chinner | 0cb9776 | 2013-08-12 20:50:09 +1000 | [diff] [blame] | 384 | * 2 byte tag field, which can be accessed using xfs_dir3_data_entry_tag_p. |
| 385 | * |
| 386 | * For dir3 structures, there is file type field between the name and the tag. |
| 387 | * This can only be manipulated by helper functions. It is packed hard against |
| 388 | * the end of the name so any padding for rounding is between the file type and |
| 389 | * the tag. |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 390 | */ |
| 391 | typedef struct xfs_dir2_data_entry { |
| 392 | __be64 inumber; /* inode number */ |
| 393 | __u8 namelen; /* name length */ |
| 394 | __u8 name[]; /* name bytes, no null */ |
Dave Chinner | 0cb9776 | 2013-08-12 20:50:09 +1000 | [diff] [blame] | 395 | /* __u8 filetype; */ /* type of inode we point to */ |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 396 | /* __be16 tag; */ /* starting offset of us */ |
| 397 | } xfs_dir2_data_entry_t; |
| 398 | |
| 399 | /* |
| 400 | * Unused entry in a data block. |
| 401 | * |
| 402 | * Aligned to 8 bytes. Tag appears as the last 2 bytes and must be accessed |
| 403 | * using xfs_dir2_data_unused_tag_p. |
| 404 | */ |
| 405 | typedef struct xfs_dir2_data_unused { |
| 406 | __be16 freetag; /* XFS_DIR2_DATA_FREE_TAG */ |
| 407 | __be16 length; /* total free length */ |
| 408 | /* variable offset */ |
| 409 | __be16 tag; /* starting offset of us */ |
| 410 | } xfs_dir2_data_unused_t; |
| 411 | |
| 412 | /* |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 413 | * Pointer to a freespace's tag word. |
| 414 | */ |
| 415 | static inline __be16 * |
| 416 | xfs_dir2_data_unused_tag_p(struct xfs_dir2_data_unused *dup) |
| 417 | { |
| 418 | return (__be16 *)((char *)dup + |
| 419 | be16_to_cpu(dup->length) - sizeof(__be16)); |
| 420 | } |
| 421 | |
Dave Chinner | f5f3d9b | 2013-04-03 16:11:20 +1100 | [diff] [blame] | 422 | /* |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 423 | * Leaf block structures. |
| 424 | * |
| 425 | * A pure leaf block looks like the following drawing on disk: |
| 426 | * |
| 427 | * +---------------------------+ |
| 428 | * | xfs_dir2_leaf_hdr_t | |
| 429 | * +---------------------------+ |
| 430 | * | xfs_dir2_leaf_entry_t | |
| 431 | * | xfs_dir2_leaf_entry_t | |
| 432 | * | xfs_dir2_leaf_entry_t | |
| 433 | * | xfs_dir2_leaf_entry_t | |
| 434 | * | ... | |
| 435 | * +---------------------------+ |
| 436 | * | xfs_dir2_data_off_t | |
| 437 | * | xfs_dir2_data_off_t | |
| 438 | * | xfs_dir2_data_off_t | |
| 439 | * | ... | |
| 440 | * +---------------------------+ |
| 441 | * | xfs_dir2_leaf_tail_t | |
| 442 | * +---------------------------+ |
| 443 | * |
| 444 | * The xfs_dir2_data_off_t members (bests) and tail are at the end of the block |
| 445 | * for single-leaf (magic = XFS_DIR2_LEAF1_MAGIC) blocks only, but not present |
| 446 | * for directories with separate leaf nodes and free space blocks |
| 447 | * (magic = XFS_DIR2_LEAFN_MAGIC). |
| 448 | * |
| 449 | * As all the entries are variable size structures the accessors below should |
| 450 | * be used to iterate over them. |
| 451 | */ |
| 452 | |
| 453 | /* |
| 454 | * Offset of the leaf/node space. First block in this space |
| 455 | * is the btree root. |
| 456 | */ |
| 457 | #define XFS_DIR2_LEAF_SPACE 1 |
| 458 | #define XFS_DIR2_LEAF_OFFSET (XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE) |
| 459 | #define XFS_DIR2_LEAF_FIRSTDB(mp) \ |
| 460 | xfs_dir2_byte_to_db(mp, XFS_DIR2_LEAF_OFFSET) |
| 461 | |
| 462 | /* |
| 463 | * Leaf block header. |
| 464 | */ |
| 465 | typedef struct xfs_dir2_leaf_hdr { |
| 466 | xfs_da_blkinfo_t info; /* header for da routines */ |
| 467 | __be16 count; /* count of entries */ |
| 468 | __be16 stale; /* count of stale entries */ |
| 469 | } xfs_dir2_leaf_hdr_t; |
| 470 | |
Dave Chinner | 24df33b | 2013-04-12 07:30:21 +1000 | [diff] [blame] | 471 | struct xfs_dir3_leaf_hdr { |
| 472 | struct xfs_da3_blkinfo info; /* header for da routines */ |
| 473 | __be16 count; /* count of entries */ |
| 474 | __be16 stale; /* count of stale entries */ |
Dave Chinner | 5170711 | 2013-06-12 12:19:07 +1000 | [diff] [blame] | 475 | __be32 pad; /* 64 bit alignment */ |
Dave Chinner | 24df33b | 2013-04-12 07:30:21 +1000 | [diff] [blame] | 476 | }; |
| 477 | |
| 478 | struct xfs_dir3_icleaf_hdr { |
| 479 | __uint32_t forw; |
| 480 | __uint32_t back; |
| 481 | __uint16_t magic; |
| 482 | __uint16_t count; |
| 483 | __uint16_t stale; |
| 484 | }; |
| 485 | |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 486 | /* |
| 487 | * Leaf block entry. |
| 488 | */ |
| 489 | typedef struct xfs_dir2_leaf_entry { |
| 490 | __be32 hashval; /* hash value of name */ |
| 491 | __be32 address; /* address of data entry */ |
| 492 | } xfs_dir2_leaf_entry_t; |
| 493 | |
| 494 | /* |
| 495 | * Leaf block tail. |
| 496 | */ |
| 497 | typedef struct xfs_dir2_leaf_tail { |
| 498 | __be32 bestcount; |
| 499 | } xfs_dir2_leaf_tail_t; |
| 500 | |
| 501 | /* |
| 502 | * Leaf block. |
| 503 | */ |
| 504 | typedef struct xfs_dir2_leaf { |
Dave Chinner | 24df33b | 2013-04-12 07:30:21 +1000 | [diff] [blame] | 505 | xfs_dir2_leaf_hdr_t hdr; /* leaf header */ |
| 506 | xfs_dir2_leaf_entry_t __ents[]; /* entries */ |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 507 | } xfs_dir2_leaf_t; |
| 508 | |
Dave Chinner | 24df33b | 2013-04-12 07:30:21 +1000 | [diff] [blame] | 509 | struct xfs_dir3_leaf { |
| 510 | struct xfs_dir3_leaf_hdr hdr; /* leaf header */ |
| 511 | struct xfs_dir2_leaf_entry __ents[]; /* entries */ |
| 512 | }; |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 513 | |
Dave Chinner | 24df33b | 2013-04-12 07:30:21 +1000 | [diff] [blame] | 514 | #define XFS_DIR3_LEAF_CRC_OFF offsetof(struct xfs_dir3_leaf_hdr, info.crc) |
| 515 | |
Dave Chinner | 24df33b | 2013-04-12 07:30:21 +1000 | [diff] [blame] | 516 | /* |
| 517 | * Get address of the bestcount field in the single-leaf block. |
| 518 | */ |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 519 | static inline struct xfs_dir2_leaf_tail * |
| 520 | xfs_dir2_leaf_tail_p(struct xfs_mount *mp, struct xfs_dir2_leaf *lp) |
| 521 | { |
| 522 | return (struct xfs_dir2_leaf_tail *) |
| 523 | ((char *)lp + mp->m_dirblksize - |
| 524 | sizeof(struct xfs_dir2_leaf_tail)); |
| 525 | } |
| 526 | |
| 527 | /* |
| 528 | * Get address of the bests array in the single-leaf block. |
| 529 | */ |
| 530 | static inline __be16 * |
| 531 | xfs_dir2_leaf_bests_p(struct xfs_dir2_leaf_tail *ltp) |
| 532 | { |
| 533 | return (__be16 *)ltp - be32_to_cpu(ltp->bestcount); |
| 534 | } |
| 535 | |
| 536 | /* |
Dave Chinner | 24df33b | 2013-04-12 07:30:21 +1000 | [diff] [blame] | 537 | * DB blocks here are logical directory block numbers, not filesystem blocks. |
| 538 | */ |
| 539 | |
| 540 | /* |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 541 | * Convert dataptr to byte in file space |
| 542 | */ |
| 543 | static inline xfs_dir2_off_t |
| 544 | xfs_dir2_dataptr_to_byte(struct xfs_mount *mp, xfs_dir2_dataptr_t dp) |
| 545 | { |
| 546 | return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG; |
| 547 | } |
| 548 | |
| 549 | /* |
| 550 | * Convert byte in file space to dataptr. It had better be aligned. |
| 551 | */ |
| 552 | static inline xfs_dir2_dataptr_t |
| 553 | xfs_dir2_byte_to_dataptr(struct xfs_mount *mp, xfs_dir2_off_t by) |
| 554 | { |
| 555 | return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG); |
| 556 | } |
| 557 | |
| 558 | /* |
| 559 | * Convert byte in space to (DB) block |
| 560 | */ |
| 561 | static inline xfs_dir2_db_t |
| 562 | xfs_dir2_byte_to_db(struct xfs_mount *mp, xfs_dir2_off_t by) |
| 563 | { |
| 564 | return (xfs_dir2_db_t) |
| 565 | (by >> (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)); |
| 566 | } |
| 567 | |
| 568 | /* |
| 569 | * Convert dataptr to a block number |
| 570 | */ |
| 571 | static inline xfs_dir2_db_t |
| 572 | xfs_dir2_dataptr_to_db(struct xfs_mount *mp, xfs_dir2_dataptr_t dp) |
| 573 | { |
| 574 | return xfs_dir2_byte_to_db(mp, xfs_dir2_dataptr_to_byte(mp, dp)); |
| 575 | } |
| 576 | |
| 577 | /* |
| 578 | * Convert byte in space to offset in a block |
| 579 | */ |
| 580 | static inline xfs_dir2_data_aoff_t |
| 581 | xfs_dir2_byte_to_off(struct xfs_mount *mp, xfs_dir2_off_t by) |
| 582 | { |
| 583 | return (xfs_dir2_data_aoff_t)(by & |
| 584 | ((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) - 1)); |
| 585 | } |
| 586 | |
| 587 | /* |
| 588 | * Convert dataptr to a byte offset in a block |
| 589 | */ |
| 590 | static inline xfs_dir2_data_aoff_t |
| 591 | xfs_dir2_dataptr_to_off(struct xfs_mount *mp, xfs_dir2_dataptr_t dp) |
| 592 | { |
| 593 | return xfs_dir2_byte_to_off(mp, xfs_dir2_dataptr_to_byte(mp, dp)); |
| 594 | } |
| 595 | |
| 596 | /* |
| 597 | * Convert block and offset to byte in space |
| 598 | */ |
| 599 | static inline xfs_dir2_off_t |
| 600 | xfs_dir2_db_off_to_byte(struct xfs_mount *mp, xfs_dir2_db_t db, |
| 601 | xfs_dir2_data_aoff_t o) |
| 602 | { |
| 603 | return ((xfs_dir2_off_t)db << |
| 604 | (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) + o; |
| 605 | } |
| 606 | |
| 607 | /* |
| 608 | * Convert block (DB) to block (dablk) |
| 609 | */ |
| 610 | static inline xfs_dablk_t |
| 611 | xfs_dir2_db_to_da(struct xfs_mount *mp, xfs_dir2_db_t db) |
| 612 | { |
| 613 | return (xfs_dablk_t)(db << mp->m_sb.sb_dirblklog); |
| 614 | } |
| 615 | |
| 616 | /* |
| 617 | * Convert byte in space to (DA) block |
| 618 | */ |
| 619 | static inline xfs_dablk_t |
| 620 | xfs_dir2_byte_to_da(struct xfs_mount *mp, xfs_dir2_off_t by) |
| 621 | { |
| 622 | return xfs_dir2_db_to_da(mp, xfs_dir2_byte_to_db(mp, by)); |
| 623 | } |
| 624 | |
| 625 | /* |
| 626 | * Convert block and offset to dataptr |
| 627 | */ |
| 628 | static inline xfs_dir2_dataptr_t |
| 629 | xfs_dir2_db_off_to_dataptr(struct xfs_mount *mp, xfs_dir2_db_t db, |
| 630 | xfs_dir2_data_aoff_t o) |
| 631 | { |
| 632 | return xfs_dir2_byte_to_dataptr(mp, xfs_dir2_db_off_to_byte(mp, db, o)); |
| 633 | } |
| 634 | |
| 635 | /* |
| 636 | * Convert block (dablk) to block (DB) |
| 637 | */ |
| 638 | static inline xfs_dir2_db_t |
| 639 | xfs_dir2_da_to_db(struct xfs_mount *mp, xfs_dablk_t da) |
| 640 | { |
| 641 | return (xfs_dir2_db_t)(da >> mp->m_sb.sb_dirblklog); |
| 642 | } |
| 643 | |
| 644 | /* |
| 645 | * Convert block (dablk) to byte offset in space |
| 646 | */ |
| 647 | static inline xfs_dir2_off_t |
| 648 | xfs_dir2_da_to_byte(struct xfs_mount *mp, xfs_dablk_t da) |
| 649 | { |
| 650 | return xfs_dir2_db_off_to_byte(mp, xfs_dir2_da_to_db(mp, da), 0); |
| 651 | } |
| 652 | |
| 653 | /* |
| 654 | * Free space block defintions for the node format. |
| 655 | */ |
| 656 | |
| 657 | /* |
| 658 | * Offset of the freespace index. |
| 659 | */ |
| 660 | #define XFS_DIR2_FREE_SPACE 2 |
| 661 | #define XFS_DIR2_FREE_OFFSET (XFS_DIR2_FREE_SPACE * XFS_DIR2_SPACE_SIZE) |
| 662 | #define XFS_DIR2_FREE_FIRSTDB(mp) \ |
| 663 | xfs_dir2_byte_to_db(mp, XFS_DIR2_FREE_OFFSET) |
| 664 | |
| 665 | typedef struct xfs_dir2_free_hdr { |
| 666 | __be32 magic; /* XFS_DIR2_FREE_MAGIC */ |
| 667 | __be32 firstdb; /* db of first entry */ |
| 668 | __be32 nvalid; /* count of valid entries */ |
| 669 | __be32 nused; /* count of used entries */ |
| 670 | } xfs_dir2_free_hdr_t; |
| 671 | |
| 672 | typedef struct xfs_dir2_free { |
| 673 | xfs_dir2_free_hdr_t hdr; /* block header */ |
Christoph Hellwig | a00b774 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 674 | __be16 bests[]; /* best free counts */ |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 675 | /* unused entries are -1 */ |
| 676 | } xfs_dir2_free_t; |
| 677 | |
Dave Chinner | cbc8adf | 2013-04-03 16:11:21 +1100 | [diff] [blame] | 678 | struct xfs_dir3_free_hdr { |
| 679 | struct xfs_dir3_blk_hdr hdr; |
| 680 | __be32 firstdb; /* db of first entry */ |
| 681 | __be32 nvalid; /* count of valid entries */ |
| 682 | __be32 nused; /* count of used entries */ |
Dave Chinner | 5170711 | 2013-06-12 12:19:07 +1000 | [diff] [blame] | 683 | __be32 pad; /* 64 bit alignment */ |
Dave Chinner | cbc8adf | 2013-04-03 16:11:21 +1100 | [diff] [blame] | 684 | }; |
| 685 | |
| 686 | struct xfs_dir3_free { |
| 687 | struct xfs_dir3_free_hdr hdr; |
| 688 | __be16 bests[]; /* best free counts */ |
| 689 | /* unused entries are -1 */ |
| 690 | }; |
| 691 | |
| 692 | #define XFS_DIR3_FREE_CRC_OFF offsetof(struct xfs_dir3_free, hdr.hdr.crc) |
| 693 | |
| 694 | /* |
| 695 | * In core version of the free block header, abstracted away from on-disk format |
| 696 | * differences. Use this in the code, and convert to/from the disk version using |
| 697 | * xfs_dir3_free_hdr_from_disk/xfs_dir3_free_hdr_to_disk. |
| 698 | */ |
| 699 | struct xfs_dir3_icfree_hdr { |
| 700 | __uint32_t magic; |
| 701 | __uint32_t firstdb; |
| 702 | __uint32_t nvalid; |
| 703 | __uint32_t nused; |
| 704 | |
| 705 | }; |
| 706 | |
Christoph Hellwig | 5792664 | 2011-07-13 13:43:48 +0200 | [diff] [blame] | 707 | /* |
| 708 | * Single block format. |
| 709 | * |
| 710 | * The single block format looks like the following drawing on disk: |
| 711 | * |
| 712 | * +-------------------------------------------------+ |
| 713 | * | xfs_dir2_data_hdr_t | |
| 714 | * +-------------------------------------------------+ |
| 715 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| 716 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | |
| 717 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t : |
| 718 | * | ... | |
| 719 | * +-------------------------------------------------+ |
| 720 | * | unused space | |
| 721 | * +-------------------------------------------------+ |
| 722 | * | ... | |
| 723 | * | xfs_dir2_leaf_entry_t | |
| 724 | * | xfs_dir2_leaf_entry_t | |
| 725 | * +-------------------------------------------------+ |
| 726 | * | xfs_dir2_block_tail_t | |
| 727 | * +-------------------------------------------------+ |
| 728 | * |
| 729 | * As all the entries are variable size structures the accessors below should |
| 730 | * be used to iterate over them. |
| 731 | */ |
| 732 | |
| 733 | typedef struct xfs_dir2_block_tail { |
| 734 | __be32 count; /* count of leaf entries */ |
| 735 | __be32 stale; /* count of stale lf entries */ |
| 736 | } xfs_dir2_block_tail_t; |
| 737 | |
| 738 | /* |
| 739 | * Pointer to the leaf header embedded in a data block (1-block format) |
| 740 | */ |
| 741 | static inline struct xfs_dir2_block_tail * |
| 742 | xfs_dir2_block_tail_p(struct xfs_mount *mp, struct xfs_dir2_data_hdr *hdr) |
| 743 | { |
| 744 | return ((struct xfs_dir2_block_tail *) |
| 745 | ((char *)hdr + mp->m_dirblksize)) - 1; |
| 746 | } |
| 747 | |
| 748 | /* |
| 749 | * Pointer to the leaf entries embedded in a data block (1-block format) |
| 750 | */ |
| 751 | static inline struct xfs_dir2_leaf_entry * |
| 752 | xfs_dir2_block_leaf_p(struct xfs_dir2_block_tail *btp) |
| 753 | { |
| 754 | return ((struct xfs_dir2_leaf_entry *)btp) - be32_to_cpu(btp->count); |
| 755 | } |
| 756 | |
Dave Chinner | 5706278 | 2013-10-15 09:17:51 +1100 | [diff] [blame] | 757 | |
| 758 | /* |
| 759 | * Attribute storage layout |
| 760 | * |
| 761 | * Attribute lists are structured around Btrees where all the data |
| 762 | * elements are in the leaf nodes. Attribute names are hashed into an int, |
| 763 | * then that int is used as the index into the Btree. Since the hashval |
| 764 | * of an attribute name may not be unique, we may have duplicate keys. The |
| 765 | * internal links in the Btree are logical block offsets into the file. |
| 766 | * |
| 767 | *======================================================================== |
| 768 | * Attribute structure when equal to XFS_LBSIZE(mp) bytes. |
| 769 | *======================================================================== |
| 770 | * |
| 771 | * Struct leaf_entry's are packed from the top. Name/values grow from the |
| 772 | * bottom but are not packed. The freemap contains run-length-encoded entries |
| 773 | * for the free bytes after the leaf_entry's, but only the N largest such, |
| 774 | * smaller runs are dropped. When the freemap doesn't show enough space |
| 775 | * for an allocation, we compact the name/value area and try again. If we |
| 776 | * still don't have enough space, then we have to split the block. The |
| 777 | * name/value structs (both local and remote versions) must be 32bit aligned. |
| 778 | * |
| 779 | * Since we have duplicate hash keys, for each key that matches, compare |
| 780 | * the actual name string. The root and intermediate node search always |
| 781 | * takes the first-in-the-block key match found, so we should only have |
| 782 | * to work "forw"ard. If none matches, continue with the "forw"ard leaf |
| 783 | * nodes until the hash key changes or the attribute name is found. |
| 784 | * |
| 785 | * We store the fact that an attribute is a ROOT/USER/SECURE attribute in |
| 786 | * the leaf_entry. The namespaces are independent only because we also look |
| 787 | * at the namespace bit when we are looking for a matching attribute name. |
| 788 | * |
| 789 | * We also store an "incomplete" bit in the leaf_entry. It shows that an |
| 790 | * attribute is in the middle of being created and should not be shown to |
| 791 | * the user if we crash during the time that the bit is set. We clear the |
| 792 | * bit when we have finished setting up the attribute. We do this because |
| 793 | * we cannot create some large attributes inside a single transaction, and we |
| 794 | * need some indication that we weren't finished if we crash in the middle. |
| 795 | */ |
| 796 | #define XFS_ATTR_LEAF_MAPSIZE 3 /* how many freespace slots */ |
| 797 | |
| 798 | typedef struct xfs_attr_leaf_map { /* RLE map of free bytes */ |
| 799 | __be16 base; /* base of free region */ |
| 800 | __be16 size; /* length of free region */ |
| 801 | } xfs_attr_leaf_map_t; |
| 802 | |
| 803 | typedef struct xfs_attr_leaf_hdr { /* constant-structure header block */ |
| 804 | xfs_da_blkinfo_t info; /* block type, links, etc. */ |
| 805 | __be16 count; /* count of active leaf_entry's */ |
| 806 | __be16 usedbytes; /* num bytes of names/values stored */ |
| 807 | __be16 firstused; /* first used byte in name area */ |
| 808 | __u8 holes; /* != 0 if blk needs compaction */ |
| 809 | __u8 pad1; |
| 810 | xfs_attr_leaf_map_t freemap[XFS_ATTR_LEAF_MAPSIZE]; |
| 811 | /* N largest free regions */ |
| 812 | } xfs_attr_leaf_hdr_t; |
| 813 | |
| 814 | typedef struct xfs_attr_leaf_entry { /* sorted on key, not name */ |
| 815 | __be32 hashval; /* hash value of name */ |
| 816 | __be16 nameidx; /* index into buffer of name/value */ |
| 817 | __u8 flags; /* LOCAL/ROOT/SECURE/INCOMPLETE flag */ |
| 818 | __u8 pad2; /* unused pad byte */ |
| 819 | } xfs_attr_leaf_entry_t; |
| 820 | |
| 821 | typedef struct xfs_attr_leaf_name_local { |
| 822 | __be16 valuelen; /* number of bytes in value */ |
| 823 | __u8 namelen; /* length of name bytes */ |
| 824 | __u8 nameval[1]; /* name/value bytes */ |
| 825 | } xfs_attr_leaf_name_local_t; |
| 826 | |
| 827 | typedef struct xfs_attr_leaf_name_remote { |
| 828 | __be32 valueblk; /* block number of value bytes */ |
| 829 | __be32 valuelen; /* number of bytes in value */ |
| 830 | __u8 namelen; /* length of name bytes */ |
| 831 | __u8 name[1]; /* name bytes */ |
| 832 | } xfs_attr_leaf_name_remote_t; |
| 833 | |
| 834 | typedef struct xfs_attr_leafblock { |
| 835 | xfs_attr_leaf_hdr_t hdr; /* constant-structure header block */ |
| 836 | xfs_attr_leaf_entry_t entries[1]; /* sorted on key, not name */ |
| 837 | xfs_attr_leaf_name_local_t namelist; /* grows from bottom of buf */ |
| 838 | xfs_attr_leaf_name_remote_t valuelist; /* grows from bottom of buf */ |
| 839 | } xfs_attr_leafblock_t; |
| 840 | |
| 841 | /* |
| 842 | * CRC enabled leaf structures. Called "version 3" structures to match the |
| 843 | * version number of the directory and dablk structures for this feature, and |
| 844 | * attr2 is already taken by the variable inode attribute fork size feature. |
| 845 | */ |
| 846 | struct xfs_attr3_leaf_hdr { |
| 847 | struct xfs_da3_blkinfo info; |
| 848 | __be16 count; |
| 849 | __be16 usedbytes; |
| 850 | __be16 firstused; |
| 851 | __u8 holes; |
| 852 | __u8 pad1; |
| 853 | struct xfs_attr_leaf_map freemap[XFS_ATTR_LEAF_MAPSIZE]; |
| 854 | __be32 pad2; /* 64 bit alignment */ |
| 855 | }; |
| 856 | |
| 857 | #define XFS_ATTR3_LEAF_CRC_OFF (offsetof(struct xfs_attr3_leaf_hdr, info.crc)) |
| 858 | |
| 859 | struct xfs_attr3_leafblock { |
| 860 | struct xfs_attr3_leaf_hdr hdr; |
| 861 | struct xfs_attr_leaf_entry entries[1]; |
| 862 | |
| 863 | /* |
| 864 | * The rest of the block contains the following structures after the |
| 865 | * leaf entries, growing from the bottom up. The variables are never |
| 866 | * referenced, the locations accessed purely from helper functions. |
| 867 | * |
| 868 | * struct xfs_attr_leaf_name_local |
| 869 | * struct xfs_attr_leaf_name_remote |
| 870 | */ |
| 871 | }; |
| 872 | |
| 873 | /* |
| 874 | * incore, neutral version of the attribute leaf header |
| 875 | */ |
| 876 | struct xfs_attr3_icleaf_hdr { |
| 877 | __uint32_t forw; |
| 878 | __uint32_t back; |
| 879 | __uint16_t magic; |
| 880 | __uint16_t count; |
| 881 | __uint16_t usedbytes; |
| 882 | __uint16_t firstused; |
| 883 | __u8 holes; |
| 884 | struct { |
| 885 | __uint16_t base; |
| 886 | __uint16_t size; |
| 887 | } freemap[XFS_ATTR_LEAF_MAPSIZE]; |
| 888 | }; |
| 889 | |
| 890 | /* |
| 891 | * Flags used in the leaf_entry[i].flags field. |
| 892 | * NOTE: the INCOMPLETE bit must not collide with the flags bits specified |
| 893 | * on the system call, they are "or"ed together for various operations. |
| 894 | */ |
| 895 | #define XFS_ATTR_LOCAL_BIT 0 /* attr is stored locally */ |
| 896 | #define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */ |
| 897 | #define XFS_ATTR_SECURE_BIT 2 /* limit access to secure attrs */ |
| 898 | #define XFS_ATTR_INCOMPLETE_BIT 7 /* attr in middle of create/delete */ |
| 899 | #define XFS_ATTR_LOCAL (1 << XFS_ATTR_LOCAL_BIT) |
| 900 | #define XFS_ATTR_ROOT (1 << XFS_ATTR_ROOT_BIT) |
| 901 | #define XFS_ATTR_SECURE (1 << XFS_ATTR_SECURE_BIT) |
| 902 | #define XFS_ATTR_INCOMPLETE (1 << XFS_ATTR_INCOMPLETE_BIT) |
| 903 | |
| 904 | /* |
| 905 | * Conversion macros for converting namespace bits from argument flags |
| 906 | * to ondisk flags. |
| 907 | */ |
| 908 | #define XFS_ATTR_NSP_ARGS_MASK (ATTR_ROOT | ATTR_SECURE) |
| 909 | #define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE) |
| 910 | #define XFS_ATTR_NSP_ONDISK(flags) ((flags) & XFS_ATTR_NSP_ONDISK_MASK) |
| 911 | #define XFS_ATTR_NSP_ARGS(flags) ((flags) & XFS_ATTR_NSP_ARGS_MASK) |
| 912 | #define XFS_ATTR_NSP_ARGS_TO_ONDISK(x) (((x) & ATTR_ROOT ? XFS_ATTR_ROOT : 0) |\ |
| 913 | ((x) & ATTR_SECURE ? XFS_ATTR_SECURE : 0)) |
| 914 | #define XFS_ATTR_NSP_ONDISK_TO_ARGS(x) (((x) & XFS_ATTR_ROOT ? ATTR_ROOT : 0) |\ |
| 915 | ((x) & XFS_ATTR_SECURE ? ATTR_SECURE : 0)) |
| 916 | |
| 917 | /* |
| 918 | * Alignment for namelist and valuelist entries (since they are mixed |
| 919 | * there can be only one alignment value) |
| 920 | */ |
| 921 | #define XFS_ATTR_LEAF_NAME_ALIGN ((uint)sizeof(xfs_dablk_t)) |
| 922 | |
| 923 | static inline int |
| 924 | xfs_attr3_leaf_hdr_size(struct xfs_attr_leafblock *leafp) |
| 925 | { |
| 926 | if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) |
| 927 | return sizeof(struct xfs_attr3_leaf_hdr); |
| 928 | return sizeof(struct xfs_attr_leaf_hdr); |
| 929 | } |
| 930 | |
| 931 | static inline struct xfs_attr_leaf_entry * |
| 932 | xfs_attr3_leaf_entryp(xfs_attr_leafblock_t *leafp) |
| 933 | { |
| 934 | if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) |
| 935 | return &((struct xfs_attr3_leafblock *)leafp)->entries[0]; |
| 936 | return &leafp->entries[0]; |
| 937 | } |
| 938 | |
| 939 | /* |
| 940 | * Cast typed pointers for "local" and "remote" name/value structs. |
| 941 | */ |
| 942 | static inline char * |
| 943 | xfs_attr3_leaf_name(xfs_attr_leafblock_t *leafp, int idx) |
| 944 | { |
| 945 | struct xfs_attr_leaf_entry *entries = xfs_attr3_leaf_entryp(leafp); |
| 946 | |
| 947 | return &((char *)leafp)[be16_to_cpu(entries[idx].nameidx)]; |
| 948 | } |
| 949 | |
| 950 | static inline xfs_attr_leaf_name_remote_t * |
| 951 | xfs_attr3_leaf_name_remote(xfs_attr_leafblock_t *leafp, int idx) |
| 952 | { |
| 953 | return (xfs_attr_leaf_name_remote_t *)xfs_attr3_leaf_name(leafp, idx); |
| 954 | } |
| 955 | |
| 956 | static inline xfs_attr_leaf_name_local_t * |
| 957 | xfs_attr3_leaf_name_local(xfs_attr_leafblock_t *leafp, int idx) |
| 958 | { |
| 959 | return (xfs_attr_leaf_name_local_t *)xfs_attr3_leaf_name(leafp, idx); |
| 960 | } |
| 961 | |
| 962 | /* |
| 963 | * Calculate total bytes used (including trailing pad for alignment) for |
| 964 | * a "local" name/value structure, a "remote" name/value structure, and |
| 965 | * a pointer which might be either. |
| 966 | */ |
| 967 | static inline int xfs_attr_leaf_entsize_remote(int nlen) |
| 968 | { |
| 969 | return ((uint)sizeof(xfs_attr_leaf_name_remote_t) - 1 + (nlen) + \ |
| 970 | XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); |
| 971 | } |
| 972 | |
| 973 | static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen) |
| 974 | { |
| 975 | return ((uint)sizeof(xfs_attr_leaf_name_local_t) - 1 + (nlen) + (vlen) + |
| 976 | XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); |
| 977 | } |
| 978 | |
| 979 | static inline int xfs_attr_leaf_entsize_local_max(int bsize) |
| 980 | { |
| 981 | return (((bsize) >> 1) + ((bsize) >> 2)); |
| 982 | } |
| 983 | |
| 984 | |
| 985 | |
| 986 | /* |
| 987 | * Remote attribute block format definition |
| 988 | * |
| 989 | * There is one of these headers per filesystem block in a remote attribute. |
| 990 | * This is done to ensure there is a 1:1 mapping between the attribute value |
| 991 | * length and the number of blocks needed to store the attribute. This makes the |
| 992 | * verification of a buffer a little more complex, but greatly simplifies the |
| 993 | * allocation, reading and writing of these attributes as we don't have to guess |
| 994 | * the number of blocks needed to store the attribute data. |
| 995 | */ |
| 996 | #define XFS_ATTR3_RMT_MAGIC 0x5841524d /* XARM */ |
| 997 | |
| 998 | struct xfs_attr3_rmt_hdr { |
| 999 | __be32 rm_magic; |
| 1000 | __be32 rm_offset; |
| 1001 | __be32 rm_bytes; |
| 1002 | __be32 rm_crc; |
| 1003 | uuid_t rm_uuid; |
| 1004 | __be64 rm_owner; |
| 1005 | __be64 rm_blkno; |
| 1006 | __be64 rm_lsn; |
| 1007 | }; |
| 1008 | |
| 1009 | #define XFS_ATTR3_RMT_CRC_OFF offsetof(struct xfs_attr3_rmt_hdr, rm_crc) |
| 1010 | |
| 1011 | #define XFS_ATTR3_RMT_BUF_SPACE(mp, bufsize) \ |
| 1012 | ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \ |
| 1013 | sizeof(struct xfs_attr3_rmt_hdr) : 0)) |
| 1014 | |
| 1015 | #endif /* __XFS_DA_FORMAT_H__ */ |