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57926640 CH |
1 | /* |
2 | * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc. | |
f5f3d9b0 | 3 | * Copyright (c) 2013 Red Hat, Inc. |
57926640 CH |
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 | */ | |
57062787 DC |
19 | #ifndef __XFS_DA_FORMAT_H__ |
20 | #define __XFS_DA_FORMAT_H__ | |
21 | ||
57062787 DC |
22 | /* |
23 | * This structure is common to both leaf nodes and non-leaf nodes in the Btree. | |
24 | * | |
25 | * It is used to manage a doubly linked list of all blocks at the same | |
26 | * level in the Btree, and to identify which type of block this is. | |
27 | */ | |
28 | #define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */ | |
29 | #define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */ | |
30 | #define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */ | |
31 | #define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */ | |
32 | ||
33 | typedef struct xfs_da_blkinfo { | |
34 | __be32 forw; /* previous block in list */ | |
35 | __be32 back; /* following block in list */ | |
36 | __be16 magic; /* validity check on block */ | |
37 | __be16 pad; /* unused */ | |
38 | } xfs_da_blkinfo_t; | |
39 | ||
40 | /* | |
41 | * CRC enabled directory structure types | |
42 | * | |
43 | * The headers change size for the additional verification information, but | |
44 | * otherwise the tree layouts and contents are unchanged. Hence the da btree | |
45 | * code can use the struct xfs_da_blkinfo for manipulating the tree links and | |
46 | * magic numbers without modification for both v2 and v3 nodes. | |
47 | */ | |
48 | #define XFS_DA3_NODE_MAGIC 0x3ebe /* magic number: non-leaf blocks */ | |
49 | #define XFS_ATTR3_LEAF_MAGIC 0x3bee /* magic number: attribute leaf blks */ | |
50 | #define XFS_DIR3_LEAF1_MAGIC 0x3df1 /* magic number: v2 dirlf single blks */ | |
51 | #define XFS_DIR3_LEAFN_MAGIC 0x3dff /* magic number: v2 dirlf multi blks */ | |
52 | ||
53 | struct xfs_da3_blkinfo { | |
54 | /* | |
55 | * the node link manipulation code relies on the fact that the first | |
56 | * element of this structure is the struct xfs_da_blkinfo so it can | |
57 | * ignore the differences in the rest of the structures. | |
58 | */ | |
59 | struct xfs_da_blkinfo hdr; | |
60 | __be32 crc; /* CRC of block */ | |
61 | __be64 blkno; /* first block of the buffer */ | |
62 | __be64 lsn; /* sequence number of last write */ | |
63 | uuid_t uuid; /* filesystem we belong to */ | |
64 | __be64 owner; /* inode that owns the block */ | |
65 | }; | |
66 | ||
67 | /* | |
68 | * This is the structure of the root and intermediate nodes in the Btree. | |
69 | * The leaf nodes are defined above. | |
70 | * | |
71 | * Entries are not packed. | |
72 | * | |
73 | * Since we have duplicate keys, use a binary search but always follow | |
74 | * all match in the block, not just the first match found. | |
75 | */ | |
76 | #define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */ | |
77 | ||
78 | typedef struct xfs_da_node_hdr { | |
79 | struct xfs_da_blkinfo info; /* block type, links, etc. */ | |
80 | __be16 __count; /* count of active entries */ | |
81 | __be16 __level; /* level above leaves (leaf == 0) */ | |
82 | } xfs_da_node_hdr_t; | |
83 | ||
84 | struct xfs_da3_node_hdr { | |
85 | struct xfs_da3_blkinfo info; /* block type, links, etc. */ | |
86 | __be16 __count; /* count of active entries */ | |
87 | __be16 __level; /* level above leaves (leaf == 0) */ | |
88 | __be32 __pad32; | |
89 | }; | |
90 | ||
91 | #define XFS_DA3_NODE_CRC_OFF (offsetof(struct xfs_da3_node_hdr, info.crc)) | |
92 | ||
93 | typedef struct xfs_da_node_entry { | |
94 | __be32 hashval; /* hash value for this descendant */ | |
95 | __be32 before; /* Btree block before this key */ | |
96 | } xfs_da_node_entry_t; | |
97 | ||
98 | typedef struct xfs_da_intnode { | |
99 | struct xfs_da_node_hdr hdr; | |
100 | struct xfs_da_node_entry __btree[]; | |
101 | } xfs_da_intnode_t; | |
102 | ||
103 | struct xfs_da3_intnode { | |
104 | struct xfs_da3_node_hdr hdr; | |
105 | struct xfs_da_node_entry __btree[]; | |
106 | }; | |
107 | ||
108 | /* | |
109 | * In-core version of the node header to abstract the differences in the v2 and | |
110 | * v3 disk format of the headers. Callers need to convert to/from disk format as | |
111 | * appropriate. | |
112 | */ | |
113 | struct xfs_da3_icnode_hdr { | |
114 | __uint32_t forw; | |
115 | __uint32_t back; | |
116 | __uint16_t magic; | |
117 | __uint16_t count; | |
118 | __uint16_t level; | |
119 | }; | |
120 | ||
57926640 CH |
121 | /* |
122 | * Directory version 2. | |
123 | * | |
124 | * There are 4 possible formats: | |
125 | * - shortform - embedded into the inode | |
126 | * - single block - data with embedded leaf at the end | |
127 | * - multiple data blocks, single leaf+freeindex block | |
128 | * - data blocks, node and leaf blocks (btree), freeindex blocks | |
129 | * | |
130 | * Note: many node blocks structures and constants are shared with the attr | |
131 | * code and defined in xfs_da_btree.h. | |
132 | */ | |
133 | ||
134 | #define XFS_DIR2_BLOCK_MAGIC 0x58443242 /* XD2B: single block dirs */ | |
135 | #define XFS_DIR2_DATA_MAGIC 0x58443244 /* XD2D: multiblock dirs */ | |
136 | #define XFS_DIR2_FREE_MAGIC 0x58443246 /* XD2F: free index blocks */ | |
137 | ||
f5f3d9b0 DC |
138 | /* |
139 | * Directory Version 3 With CRCs. | |
140 | * | |
141 | * The tree formats are the same as for version 2 directories. The difference | |
142 | * is in the block header and dirent formats. In many cases the v3 structures | |
143 | * use v2 definitions as they are no different and this makes code sharing much | |
144 | * easier. | |
145 | * | |
146 | * Also, the xfs_dir3_*() functions handle both v2 and v3 formats - if the | |
147 | * format is v2 then they switch to the existing v2 code, or the format is v3 | |
148 | * they implement the v3 functionality. This means the existing dir2 is a mix of | |
149 | * xfs_dir2/xfs_dir3 calls and functions. The xfs_dir3 functions are called | |
150 | * where there is a difference in the formats, otherwise the code is unchanged. | |
151 | * | |
152 | * Where it is possible, the code decides what to do based on the magic numbers | |
153 | * in the blocks rather than feature bits in the superblock. This means the code | |
154 | * is as independent of the external XFS code as possible as doesn't require | |
155 | * passing struct xfs_mount pointers into places where it isn't really | |
156 | * necessary. | |
157 | * | |
158 | * Version 3 includes: | |
159 | * | |
160 | * - a larger block header for CRC and identification purposes and so the | |
161 | * offsets of all the structures inside the blocks are different. | |
162 | * | |
163 | * - new magic numbers to be able to detect the v2/v3 types on the fly. | |
164 | */ | |
165 | ||
166 | #define XFS_DIR3_BLOCK_MAGIC 0x58444233 /* XDB3: single block dirs */ | |
167 | #define XFS_DIR3_DATA_MAGIC 0x58444433 /* XDD3: multiblock dirs */ | |
cbc8adf8 | 168 | #define XFS_DIR3_FREE_MAGIC 0x58444633 /* XDF3: free index blocks */ |
f5f3d9b0 | 169 | |
0cb97766 DC |
170 | /* |
171 | * Dirents in version 3 directories have a file type field. Additions to this | |
172 | * list are an on-disk format change, requiring feature bits. Valid values | |
173 | * are as follows: | |
174 | */ | |
175 | #define XFS_DIR3_FT_UNKNOWN 0 | |
176 | #define XFS_DIR3_FT_REG_FILE 1 | |
177 | #define XFS_DIR3_FT_DIR 2 | |
178 | #define XFS_DIR3_FT_CHRDEV 3 | |
179 | #define XFS_DIR3_FT_BLKDEV 4 | |
180 | #define XFS_DIR3_FT_FIFO 5 | |
181 | #define XFS_DIR3_FT_SOCK 6 | |
182 | #define XFS_DIR3_FT_SYMLINK 7 | |
183 | #define XFS_DIR3_FT_WHT 8 | |
184 | ||
185 | #define XFS_DIR3_FT_MAX 9 | |
186 | ||
57926640 CH |
187 | /* |
188 | * Byte offset in data block and shortform entry. | |
189 | */ | |
190 | typedef __uint16_t xfs_dir2_data_off_t; | |
191 | #define NULLDATAOFF 0xffffU | |
192 | typedef uint xfs_dir2_data_aoff_t; /* argument form */ | |
193 | ||
194 | /* | |
195 | * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t. | |
196 | * Only need 16 bits, this is the byte offset into the single block form. | |
197 | */ | |
198 | typedef struct { __uint8_t i[2]; } __arch_pack xfs_dir2_sf_off_t; | |
199 | ||
200 | /* | |
201 | * Offset in data space of a data entry. | |
202 | */ | |
203 | typedef __uint32_t xfs_dir2_dataptr_t; | |
204 | #define XFS_DIR2_MAX_DATAPTR ((xfs_dir2_dataptr_t)0xffffffff) | |
205 | #define XFS_DIR2_NULL_DATAPTR ((xfs_dir2_dataptr_t)0) | |
206 | ||
207 | /* | |
208 | * Byte offset in a directory. | |
209 | */ | |
210 | typedef xfs_off_t xfs_dir2_off_t; | |
211 | ||
212 | /* | |
213 | * Directory block number (logical dirblk in file) | |
214 | */ | |
215 | typedef __uint32_t xfs_dir2_db_t; | |
216 | ||
217 | /* | |
218 | * Inode number stored as 8 8-bit values. | |
219 | */ | |
220 | typedef struct { __uint8_t i[8]; } xfs_dir2_ino8_t; | |
221 | ||
222 | /* | |
223 | * Inode number stored as 4 8-bit values. | |
224 | * Works a lot of the time, when all the inode numbers in a directory | |
225 | * fit in 32 bits. | |
226 | */ | |
227 | typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t; | |
228 | ||
229 | typedef union { | |
230 | xfs_dir2_ino8_t i8; | |
231 | xfs_dir2_ino4_t i4; | |
232 | } xfs_dir2_inou_t; | |
233 | #define XFS_DIR2_MAX_SHORT_INUM ((xfs_ino_t)0xffffffffULL) | |
234 | ||
235 | /* | |
236 | * Directory layout when stored internal to an inode. | |
237 | * | |
238 | * Small directories are packed as tightly as possible so as to fit into the | |
239 | * literal area of the inode. These "shortform" directories consist of a | |
240 | * single xfs_dir2_sf_hdr header followed by zero or more xfs_dir2_sf_entry | |
241 | * structures. Due the different inode number storage size and the variable | |
242 | * length name field in the xfs_dir2_sf_entry all these structure are | |
243 | * variable length, and the accessors in this file should be used to iterate | |
244 | * over them. | |
245 | */ | |
246 | typedef struct xfs_dir2_sf_hdr { | |
247 | __uint8_t count; /* count of entries */ | |
248 | __uint8_t i8count; /* count of 8-byte inode #s */ | |
249 | xfs_dir2_inou_t parent; /* parent dir inode number */ | |
250 | } __arch_pack xfs_dir2_sf_hdr_t; | |
251 | ||
252 | typedef struct xfs_dir2_sf_entry { | |
253 | __u8 namelen; /* actual name length */ | |
254 | xfs_dir2_sf_off_t offset; /* saved offset */ | |
255 | __u8 name[]; /* name, variable size */ | |
256 | /* | |
0cb97766 DC |
257 | * A single byte containing the file type field follows the inode |
258 | * number for version 3 directory entries. | |
259 | * | |
57926640 CH |
260 | * A xfs_dir2_ino8_t or xfs_dir2_ino4_t follows here, at a |
261 | * variable offset after the name. | |
262 | */ | |
263 | } __arch_pack xfs_dir2_sf_entry_t; | |
264 | ||
265 | static inline int xfs_dir2_sf_hdr_size(int i8count) | |
266 | { | |
267 | return sizeof(struct xfs_dir2_sf_hdr) - | |
268 | (i8count == 0) * | |
269 | (sizeof(xfs_dir2_ino8_t) - sizeof(xfs_dir2_ino4_t)); | |
270 | } | |
271 | ||
272 | static inline xfs_dir2_data_aoff_t | |
273 | xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep) | |
274 | { | |
275 | return get_unaligned_be16(&sfep->offset.i); | |
276 | } | |
277 | ||
278 | static inline void | |
279 | xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off) | |
280 | { | |
281 | put_unaligned_be16(off, &sfep->offset.i); | |
282 | } | |
283 | ||
57926640 CH |
284 | static inline struct xfs_dir2_sf_entry * |
285 | xfs_dir2_sf_firstentry(struct xfs_dir2_sf_hdr *hdr) | |
286 | { | |
287 | return (struct xfs_dir2_sf_entry *) | |
288 | ((char *)hdr + xfs_dir2_sf_hdr_size(hdr->i8count)); | |
289 | } | |
290 | ||
57926640 CH |
291 | /* |
292 | * Data block structures. | |
293 | * | |
294 | * A pure data block looks like the following drawing on disk: | |
295 | * | |
296 | * +-------------------------------------------------+ | |
297 | * | xfs_dir2_data_hdr_t | | |
298 | * +-------------------------------------------------+ | |
299 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | | |
300 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | | |
301 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | | |
302 | * | ... | | |
303 | * +-------------------------------------------------+ | |
304 | * | unused space | | |
305 | * +-------------------------------------------------+ | |
306 | * | |
307 | * As all the entries are variable size structures the accessors below should | |
308 | * be used to iterate over them. | |
309 | * | |
310 | * In addition to the pure data blocks for the data and node formats, | |
311 | * most structures are also used for the combined data/freespace "block" | |
312 | * format below. | |
313 | */ | |
314 | ||
315 | #define XFS_DIR2_DATA_ALIGN_LOG 3 /* i.e., 8 bytes */ | |
316 | #define XFS_DIR2_DATA_ALIGN (1 << XFS_DIR2_DATA_ALIGN_LOG) | |
317 | #define XFS_DIR2_DATA_FREE_TAG 0xffff | |
318 | #define XFS_DIR2_DATA_FD_COUNT 3 | |
319 | ||
320 | /* | |
321 | * Directory address space divided into sections, | |
322 | * spaces separated by 32GB. | |
323 | */ | |
324 | #define XFS_DIR2_SPACE_SIZE (1ULL << (32 + XFS_DIR2_DATA_ALIGN_LOG)) | |
325 | #define XFS_DIR2_DATA_SPACE 0 | |
326 | #define XFS_DIR2_DATA_OFFSET (XFS_DIR2_DATA_SPACE * XFS_DIR2_SPACE_SIZE) | |
57926640 | 327 | |
57926640 CH |
328 | /* |
329 | * Describe a free area in the data block. | |
330 | * | |
331 | * The freespace will be formatted as a xfs_dir2_data_unused_t. | |
332 | */ | |
333 | typedef struct xfs_dir2_data_free { | |
334 | __be16 offset; /* start of freespace */ | |
335 | __be16 length; /* length of freespace */ | |
336 | } xfs_dir2_data_free_t; | |
337 | ||
338 | /* | |
339 | * Header for the data blocks. | |
340 | * | |
341 | * The code knows that XFS_DIR2_DATA_FD_COUNT is 3. | |
342 | */ | |
343 | typedef struct xfs_dir2_data_hdr { | |
344 | __be32 magic; /* XFS_DIR2_DATA_MAGIC or */ | |
345 | /* XFS_DIR2_BLOCK_MAGIC */ | |
346 | xfs_dir2_data_free_t bestfree[XFS_DIR2_DATA_FD_COUNT]; | |
347 | } xfs_dir2_data_hdr_t; | |
348 | ||
f5f3d9b0 DC |
349 | /* |
350 | * define a structure for all the verification fields we are adding to the | |
351 | * directory block structures. This will be used in several structures. | |
352 | * The magic number must be the first entry to align with all the dir2 | |
353 | * structures so we determine how to decode them just by the magic number. | |
354 | */ | |
355 | struct xfs_dir3_blk_hdr { | |
356 | __be32 magic; /* magic number */ | |
357 | __be32 crc; /* CRC of block */ | |
358 | __be64 blkno; /* first block of the buffer */ | |
359 | __be64 lsn; /* sequence number of last write */ | |
360 | uuid_t uuid; /* filesystem we belong to */ | |
361 | __be64 owner; /* inode that owns the block */ | |
362 | }; | |
363 | ||
364 | struct xfs_dir3_data_hdr { | |
365 | struct xfs_dir3_blk_hdr hdr; | |
366 | xfs_dir2_data_free_t best_free[XFS_DIR2_DATA_FD_COUNT]; | |
5170711d | 367 | __be32 pad; /* 64 bit alignment */ |
f5f3d9b0 DC |
368 | }; |
369 | ||
370 | #define XFS_DIR3_DATA_CRC_OFF offsetof(struct xfs_dir3_data_hdr, hdr.crc) | |
371 | ||
57926640 CH |
372 | /* |
373 | * Active entry in a data block. | |
374 | * | |
375 | * Aligned to 8 bytes. After the variable length name field there is a | |
0cb97766 DC |
376 | * 2 byte tag field, which can be accessed using xfs_dir3_data_entry_tag_p. |
377 | * | |
378 | * For dir3 structures, there is file type field between the name and the tag. | |
379 | * This can only be manipulated by helper functions. It is packed hard against | |
380 | * the end of the name so any padding for rounding is between the file type and | |
381 | * the tag. | |
57926640 CH |
382 | */ |
383 | typedef struct xfs_dir2_data_entry { | |
384 | __be64 inumber; /* inode number */ | |
385 | __u8 namelen; /* name length */ | |
386 | __u8 name[]; /* name bytes, no null */ | |
0cb97766 | 387 | /* __u8 filetype; */ /* type of inode we point to */ |
57926640 CH |
388 | /* __be16 tag; */ /* starting offset of us */ |
389 | } xfs_dir2_data_entry_t; | |
390 | ||
391 | /* | |
392 | * Unused entry in a data block. | |
393 | * | |
394 | * Aligned to 8 bytes. Tag appears as the last 2 bytes and must be accessed | |
395 | * using xfs_dir2_data_unused_tag_p. | |
396 | */ | |
397 | typedef struct xfs_dir2_data_unused { | |
398 | __be16 freetag; /* XFS_DIR2_DATA_FREE_TAG */ | |
399 | __be16 length; /* total free length */ | |
400 | /* variable offset */ | |
401 | __be16 tag; /* starting offset of us */ | |
402 | } xfs_dir2_data_unused_t; | |
403 | ||
57926640 CH |
404 | /* |
405 | * Pointer to a freespace's tag word. | |
406 | */ | |
407 | static inline __be16 * | |
408 | xfs_dir2_data_unused_tag_p(struct xfs_dir2_data_unused *dup) | |
409 | { | |
410 | return (__be16 *)((char *)dup + | |
411 | be16_to_cpu(dup->length) - sizeof(__be16)); | |
412 | } | |
413 | ||
414 | /* | |
415 | * Leaf block structures. | |
416 | * | |
417 | * A pure leaf block looks like the following drawing on disk: | |
418 | * | |
419 | * +---------------------------+ | |
420 | * | xfs_dir2_leaf_hdr_t | | |
421 | * +---------------------------+ | |
422 | * | xfs_dir2_leaf_entry_t | | |
423 | * | xfs_dir2_leaf_entry_t | | |
424 | * | xfs_dir2_leaf_entry_t | | |
425 | * | xfs_dir2_leaf_entry_t | | |
426 | * | ... | | |
427 | * +---------------------------+ | |
428 | * | xfs_dir2_data_off_t | | |
429 | * | xfs_dir2_data_off_t | | |
430 | * | xfs_dir2_data_off_t | | |
431 | * | ... | | |
432 | * +---------------------------+ | |
433 | * | xfs_dir2_leaf_tail_t | | |
434 | * +---------------------------+ | |
435 | * | |
436 | * The xfs_dir2_data_off_t members (bests) and tail are at the end of the block | |
437 | * for single-leaf (magic = XFS_DIR2_LEAF1_MAGIC) blocks only, but not present | |
438 | * for directories with separate leaf nodes and free space blocks | |
439 | * (magic = XFS_DIR2_LEAFN_MAGIC). | |
440 | * | |
441 | * As all the entries are variable size structures the accessors below should | |
442 | * be used to iterate over them. | |
443 | */ | |
444 | ||
445 | /* | |
446 | * Offset of the leaf/node space. First block in this space | |
447 | * is the btree root. | |
448 | */ | |
449 | #define XFS_DIR2_LEAF_SPACE 1 | |
450 | #define XFS_DIR2_LEAF_OFFSET (XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE) | |
57926640 CH |
451 | |
452 | /* | |
453 | * Leaf block header. | |
454 | */ | |
455 | typedef struct xfs_dir2_leaf_hdr { | |
456 | xfs_da_blkinfo_t info; /* header for da routines */ | |
457 | __be16 count; /* count of entries */ | |
458 | __be16 stale; /* count of stale entries */ | |
459 | } xfs_dir2_leaf_hdr_t; | |
460 | ||
24df33b4 DC |
461 | struct xfs_dir3_leaf_hdr { |
462 | struct xfs_da3_blkinfo info; /* header for da routines */ | |
463 | __be16 count; /* count of entries */ | |
464 | __be16 stale; /* count of stale entries */ | |
5170711d | 465 | __be32 pad; /* 64 bit alignment */ |
24df33b4 DC |
466 | }; |
467 | ||
468 | struct xfs_dir3_icleaf_hdr { | |
469 | __uint32_t forw; | |
470 | __uint32_t back; | |
471 | __uint16_t magic; | |
472 | __uint16_t count; | |
473 | __uint16_t stale; | |
474 | }; | |
475 | ||
57926640 CH |
476 | /* |
477 | * Leaf block entry. | |
478 | */ | |
479 | typedef struct xfs_dir2_leaf_entry { | |
480 | __be32 hashval; /* hash value of name */ | |
481 | __be32 address; /* address of data entry */ | |
482 | } xfs_dir2_leaf_entry_t; | |
483 | ||
484 | /* | |
485 | * Leaf block tail. | |
486 | */ | |
487 | typedef struct xfs_dir2_leaf_tail { | |
488 | __be32 bestcount; | |
489 | } xfs_dir2_leaf_tail_t; | |
490 | ||
491 | /* | |
492 | * Leaf block. | |
493 | */ | |
494 | typedef struct xfs_dir2_leaf { | |
24df33b4 DC |
495 | xfs_dir2_leaf_hdr_t hdr; /* leaf header */ |
496 | xfs_dir2_leaf_entry_t __ents[]; /* entries */ | |
57926640 CH |
497 | } xfs_dir2_leaf_t; |
498 | ||
24df33b4 DC |
499 | struct xfs_dir3_leaf { |
500 | struct xfs_dir3_leaf_hdr hdr; /* leaf header */ | |
501 | struct xfs_dir2_leaf_entry __ents[]; /* entries */ | |
502 | }; | |
503 | ||
504 | #define XFS_DIR3_LEAF_CRC_OFF offsetof(struct xfs_dir3_leaf_hdr, info.crc) | |
57926640 | 505 | |
57926640 CH |
506 | /* |
507 | * Get address of the bests array in the single-leaf block. | |
508 | */ | |
509 | static inline __be16 * | |
510 | xfs_dir2_leaf_bests_p(struct xfs_dir2_leaf_tail *ltp) | |
511 | { | |
512 | return (__be16 *)ltp - be32_to_cpu(ltp->bestcount); | |
513 | } | |
514 | ||
57926640 CH |
515 | /* |
516 | * Free space block defintions for the node format. | |
517 | */ | |
518 | ||
519 | /* | |
520 | * Offset of the freespace index. | |
521 | */ | |
522 | #define XFS_DIR2_FREE_SPACE 2 | |
523 | #define XFS_DIR2_FREE_OFFSET (XFS_DIR2_FREE_SPACE * XFS_DIR2_SPACE_SIZE) | |
57926640 CH |
524 | |
525 | typedef struct xfs_dir2_free_hdr { | |
526 | __be32 magic; /* XFS_DIR2_FREE_MAGIC */ | |
527 | __be32 firstdb; /* db of first entry */ | |
528 | __be32 nvalid; /* count of valid entries */ | |
529 | __be32 nused; /* count of used entries */ | |
530 | } xfs_dir2_free_hdr_t; | |
531 | ||
532 | typedef struct xfs_dir2_free { | |
533 | xfs_dir2_free_hdr_t hdr; /* block header */ | |
a00b7745 | 534 | __be16 bests[]; /* best free counts */ |
57926640 CH |
535 | /* unused entries are -1 */ |
536 | } xfs_dir2_free_t; | |
537 | ||
cbc8adf8 DC |
538 | struct xfs_dir3_free_hdr { |
539 | struct xfs_dir3_blk_hdr hdr; | |
540 | __be32 firstdb; /* db of first entry */ | |
541 | __be32 nvalid; /* count of valid entries */ | |
542 | __be32 nused; /* count of used entries */ | |
5170711d | 543 | __be32 pad; /* 64 bit alignment */ |
cbc8adf8 DC |
544 | }; |
545 | ||
546 | struct xfs_dir3_free { | |
547 | struct xfs_dir3_free_hdr hdr; | |
548 | __be16 bests[]; /* best free counts */ | |
549 | /* unused entries are -1 */ | |
550 | }; | |
551 | ||
552 | #define XFS_DIR3_FREE_CRC_OFF offsetof(struct xfs_dir3_free, hdr.hdr.crc) | |
553 | ||
554 | /* | |
555 | * In core version of the free block header, abstracted away from on-disk format | |
556 | * differences. Use this in the code, and convert to/from the disk version using | |
557 | * xfs_dir3_free_hdr_from_disk/xfs_dir3_free_hdr_to_disk. | |
558 | */ | |
559 | struct xfs_dir3_icfree_hdr { | |
560 | __uint32_t magic; | |
561 | __uint32_t firstdb; | |
562 | __uint32_t nvalid; | |
563 | __uint32_t nused; | |
564 | ||
565 | }; | |
566 | ||
57926640 CH |
567 | /* |
568 | * Single block format. | |
569 | * | |
570 | * The single block format looks like the following drawing on disk: | |
571 | * | |
572 | * +-------------------------------------------------+ | |
573 | * | xfs_dir2_data_hdr_t | | |
574 | * +-------------------------------------------------+ | |
575 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | | |
576 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | | |
577 | * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t : | |
578 | * | ... | | |
579 | * +-------------------------------------------------+ | |
580 | * | unused space | | |
581 | * +-------------------------------------------------+ | |
582 | * | ... | | |
583 | * | xfs_dir2_leaf_entry_t | | |
584 | * | xfs_dir2_leaf_entry_t | | |
585 | * +-------------------------------------------------+ | |
586 | * | xfs_dir2_block_tail_t | | |
587 | * +-------------------------------------------------+ | |
588 | * | |
589 | * As all the entries are variable size structures the accessors below should | |
590 | * be used to iterate over them. | |
591 | */ | |
592 | ||
593 | typedef struct xfs_dir2_block_tail { | |
594 | __be32 count; /* count of leaf entries */ | |
595 | __be32 stale; /* count of stale lf entries */ | |
596 | } xfs_dir2_block_tail_t; | |
597 | ||
57926640 CH |
598 | /* |
599 | * Pointer to the leaf entries embedded in a data block (1-block format) | |
600 | */ | |
601 | static inline struct xfs_dir2_leaf_entry * | |
602 | xfs_dir2_block_leaf_p(struct xfs_dir2_block_tail *btp) | |
603 | { | |
604 | return ((struct xfs_dir2_leaf_entry *)btp) - be32_to_cpu(btp->count); | |
605 | } | |
606 | ||
57062787 DC |
607 | |
608 | /* | |
609 | * Attribute storage layout | |
610 | * | |
611 | * Attribute lists are structured around Btrees where all the data | |
612 | * elements are in the leaf nodes. Attribute names are hashed into an int, | |
613 | * then that int is used as the index into the Btree. Since the hashval | |
614 | * of an attribute name may not be unique, we may have duplicate keys. The | |
615 | * internal links in the Btree are logical block offsets into the file. | |
616 | * | |
57062787 DC |
617 | * Struct leaf_entry's are packed from the top. Name/values grow from the |
618 | * bottom but are not packed. The freemap contains run-length-encoded entries | |
619 | * for the free bytes after the leaf_entry's, but only the N largest such, | |
620 | * smaller runs are dropped. When the freemap doesn't show enough space | |
621 | * for an allocation, we compact the name/value area and try again. If we | |
622 | * still don't have enough space, then we have to split the block. The | |
623 | * name/value structs (both local and remote versions) must be 32bit aligned. | |
624 | * | |
625 | * Since we have duplicate hash keys, for each key that matches, compare | |
626 | * the actual name string. The root and intermediate node search always | |
627 | * takes the first-in-the-block key match found, so we should only have | |
628 | * to work "forw"ard. If none matches, continue with the "forw"ard leaf | |
629 | * nodes until the hash key changes or the attribute name is found. | |
630 | * | |
631 | * We store the fact that an attribute is a ROOT/USER/SECURE attribute in | |
632 | * the leaf_entry. The namespaces are independent only because we also look | |
633 | * at the namespace bit when we are looking for a matching attribute name. | |
634 | * | |
635 | * We also store an "incomplete" bit in the leaf_entry. It shows that an | |
636 | * attribute is in the middle of being created and should not be shown to | |
637 | * the user if we crash during the time that the bit is set. We clear the | |
638 | * bit when we have finished setting up the attribute. We do this because | |
639 | * we cannot create some large attributes inside a single transaction, and we | |
640 | * need some indication that we weren't finished if we crash in the middle. | |
641 | */ | |
642 | #define XFS_ATTR_LEAF_MAPSIZE 3 /* how many freespace slots */ | |
643 | ||
644 | typedef struct xfs_attr_leaf_map { /* RLE map of free bytes */ | |
645 | __be16 base; /* base of free region */ | |
646 | __be16 size; /* length of free region */ | |
647 | } xfs_attr_leaf_map_t; | |
648 | ||
649 | typedef struct xfs_attr_leaf_hdr { /* constant-structure header block */ | |
650 | xfs_da_blkinfo_t info; /* block type, links, etc. */ | |
651 | __be16 count; /* count of active leaf_entry's */ | |
652 | __be16 usedbytes; /* num bytes of names/values stored */ | |
653 | __be16 firstused; /* first used byte in name area */ | |
654 | __u8 holes; /* != 0 if blk needs compaction */ | |
655 | __u8 pad1; | |
656 | xfs_attr_leaf_map_t freemap[XFS_ATTR_LEAF_MAPSIZE]; | |
657 | /* N largest free regions */ | |
658 | } xfs_attr_leaf_hdr_t; | |
659 | ||
660 | typedef struct xfs_attr_leaf_entry { /* sorted on key, not name */ | |
661 | __be32 hashval; /* hash value of name */ | |
662 | __be16 nameidx; /* index into buffer of name/value */ | |
663 | __u8 flags; /* LOCAL/ROOT/SECURE/INCOMPLETE flag */ | |
664 | __u8 pad2; /* unused pad byte */ | |
665 | } xfs_attr_leaf_entry_t; | |
666 | ||
667 | typedef struct xfs_attr_leaf_name_local { | |
668 | __be16 valuelen; /* number of bytes in value */ | |
669 | __u8 namelen; /* length of name bytes */ | |
670 | __u8 nameval[1]; /* name/value bytes */ | |
671 | } xfs_attr_leaf_name_local_t; | |
672 | ||
673 | typedef struct xfs_attr_leaf_name_remote { | |
674 | __be32 valueblk; /* block number of value bytes */ | |
675 | __be32 valuelen; /* number of bytes in value */ | |
676 | __u8 namelen; /* length of name bytes */ | |
677 | __u8 name[1]; /* name bytes */ | |
678 | } xfs_attr_leaf_name_remote_t; | |
679 | ||
680 | typedef struct xfs_attr_leafblock { | |
681 | xfs_attr_leaf_hdr_t hdr; /* constant-structure header block */ | |
682 | xfs_attr_leaf_entry_t entries[1]; /* sorted on key, not name */ | |
ffeecc52 JK |
683 | /* |
684 | * The rest of the block contains the following structures after the | |
685 | * leaf entries, growing from the bottom up. The variables are never | |
686 | * referenced and definining them can actually make gcc optimize away | |
687 | * accesses to the 'entries' array above index 0 so don't do that. | |
688 | * | |
689 | * xfs_attr_leaf_name_local_t namelist; | |
690 | * xfs_attr_leaf_name_remote_t valuelist; | |
691 | */ | |
57062787 DC |
692 | } xfs_attr_leafblock_t; |
693 | ||
694 | /* | |
695 | * CRC enabled leaf structures. Called "version 3" structures to match the | |
696 | * version number of the directory and dablk structures for this feature, and | |
697 | * attr2 is already taken by the variable inode attribute fork size feature. | |
698 | */ | |
699 | struct xfs_attr3_leaf_hdr { | |
700 | struct xfs_da3_blkinfo info; | |
701 | __be16 count; | |
702 | __be16 usedbytes; | |
703 | __be16 firstused; | |
704 | __u8 holes; | |
705 | __u8 pad1; | |
706 | struct xfs_attr_leaf_map freemap[XFS_ATTR_LEAF_MAPSIZE]; | |
707 | __be32 pad2; /* 64 bit alignment */ | |
708 | }; | |
709 | ||
710 | #define XFS_ATTR3_LEAF_CRC_OFF (offsetof(struct xfs_attr3_leaf_hdr, info.crc)) | |
711 | ||
712 | struct xfs_attr3_leafblock { | |
713 | struct xfs_attr3_leaf_hdr hdr; | |
714 | struct xfs_attr_leaf_entry entries[1]; | |
715 | ||
716 | /* | |
717 | * The rest of the block contains the following structures after the | |
718 | * leaf entries, growing from the bottom up. The variables are never | |
719 | * referenced, the locations accessed purely from helper functions. | |
720 | * | |
721 | * struct xfs_attr_leaf_name_local | |
722 | * struct xfs_attr_leaf_name_remote | |
723 | */ | |
724 | }; | |
725 | ||
726 | /* | |
727 | * incore, neutral version of the attribute leaf header | |
728 | */ | |
729 | struct xfs_attr3_icleaf_hdr { | |
730 | __uint32_t forw; | |
731 | __uint32_t back; | |
732 | __uint16_t magic; | |
733 | __uint16_t count; | |
734 | __uint16_t usedbytes; | |
e87021a2 BF |
735 | /* |
736 | * firstused is 32-bit here instead of 16-bit like the on-disk variant | |
737 | * to support maximum fsb size of 64k without overflow issues throughout | |
738 | * the attr code. Instead, the overflow condition is handled on | |
739 | * conversion to/from disk. | |
740 | */ | |
741 | __uint32_t firstused; | |
57062787 DC |
742 | __u8 holes; |
743 | struct { | |
744 | __uint16_t base; | |
745 | __uint16_t size; | |
746 | } freemap[XFS_ATTR_LEAF_MAPSIZE]; | |
747 | }; | |
748 | ||
e87021a2 BF |
749 | /* |
750 | * Special value to represent fs block size in the leaf header firstused field. | |
751 | * Only used when block size overflows the 2-bytes available on disk. | |
752 | */ | |
753 | #define XFS_ATTR3_LEAF_NULLOFF 0 | |
754 | ||
57062787 DC |
755 | /* |
756 | * Flags used in the leaf_entry[i].flags field. | |
757 | * NOTE: the INCOMPLETE bit must not collide with the flags bits specified | |
758 | * on the system call, they are "or"ed together for various operations. | |
759 | */ | |
760 | #define XFS_ATTR_LOCAL_BIT 0 /* attr is stored locally */ | |
761 | #define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */ | |
762 | #define XFS_ATTR_SECURE_BIT 2 /* limit access to secure attrs */ | |
763 | #define XFS_ATTR_INCOMPLETE_BIT 7 /* attr in middle of create/delete */ | |
764 | #define XFS_ATTR_LOCAL (1 << XFS_ATTR_LOCAL_BIT) | |
765 | #define XFS_ATTR_ROOT (1 << XFS_ATTR_ROOT_BIT) | |
766 | #define XFS_ATTR_SECURE (1 << XFS_ATTR_SECURE_BIT) | |
767 | #define XFS_ATTR_INCOMPLETE (1 << XFS_ATTR_INCOMPLETE_BIT) | |
768 | ||
769 | /* | |
770 | * Conversion macros for converting namespace bits from argument flags | |
771 | * to ondisk flags. | |
772 | */ | |
773 | #define XFS_ATTR_NSP_ARGS_MASK (ATTR_ROOT | ATTR_SECURE) | |
774 | #define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE) | |
775 | #define XFS_ATTR_NSP_ONDISK(flags) ((flags) & XFS_ATTR_NSP_ONDISK_MASK) | |
776 | #define XFS_ATTR_NSP_ARGS(flags) ((flags) & XFS_ATTR_NSP_ARGS_MASK) | |
777 | #define XFS_ATTR_NSP_ARGS_TO_ONDISK(x) (((x) & ATTR_ROOT ? XFS_ATTR_ROOT : 0) |\ | |
778 | ((x) & ATTR_SECURE ? XFS_ATTR_SECURE : 0)) | |
779 | #define XFS_ATTR_NSP_ONDISK_TO_ARGS(x) (((x) & XFS_ATTR_ROOT ? ATTR_ROOT : 0) |\ | |
780 | ((x) & XFS_ATTR_SECURE ? ATTR_SECURE : 0)) | |
781 | ||
782 | /* | |
783 | * Alignment for namelist and valuelist entries (since they are mixed | |
784 | * there can be only one alignment value) | |
785 | */ | |
786 | #define XFS_ATTR_LEAF_NAME_ALIGN ((uint)sizeof(xfs_dablk_t)) | |
787 | ||
788 | static inline int | |
789 | xfs_attr3_leaf_hdr_size(struct xfs_attr_leafblock *leafp) | |
790 | { | |
791 | if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) | |
792 | return sizeof(struct xfs_attr3_leaf_hdr); | |
793 | return sizeof(struct xfs_attr_leaf_hdr); | |
794 | } | |
795 | ||
796 | static inline struct xfs_attr_leaf_entry * | |
797 | xfs_attr3_leaf_entryp(xfs_attr_leafblock_t *leafp) | |
798 | { | |
799 | if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) | |
800 | return &((struct xfs_attr3_leafblock *)leafp)->entries[0]; | |
801 | return &leafp->entries[0]; | |
802 | } | |
803 | ||
804 | /* | |
805 | * Cast typed pointers for "local" and "remote" name/value structs. | |
806 | */ | |
807 | static inline char * | |
808 | xfs_attr3_leaf_name(xfs_attr_leafblock_t *leafp, int idx) | |
809 | { | |
810 | struct xfs_attr_leaf_entry *entries = xfs_attr3_leaf_entryp(leafp); | |
811 | ||
812 | return &((char *)leafp)[be16_to_cpu(entries[idx].nameidx)]; | |
813 | } | |
814 | ||
815 | static inline xfs_attr_leaf_name_remote_t * | |
816 | xfs_attr3_leaf_name_remote(xfs_attr_leafblock_t *leafp, int idx) | |
817 | { | |
818 | return (xfs_attr_leaf_name_remote_t *)xfs_attr3_leaf_name(leafp, idx); | |
819 | } | |
820 | ||
821 | static inline xfs_attr_leaf_name_local_t * | |
822 | xfs_attr3_leaf_name_local(xfs_attr_leafblock_t *leafp, int idx) | |
823 | { | |
824 | return (xfs_attr_leaf_name_local_t *)xfs_attr3_leaf_name(leafp, idx); | |
825 | } | |
826 | ||
827 | /* | |
828 | * Calculate total bytes used (including trailing pad for alignment) for | |
829 | * a "local" name/value structure, a "remote" name/value structure, and | |
830 | * a pointer which might be either. | |
831 | */ | |
832 | static inline int xfs_attr_leaf_entsize_remote(int nlen) | |
833 | { | |
834 | return ((uint)sizeof(xfs_attr_leaf_name_remote_t) - 1 + (nlen) + \ | |
835 | XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); | |
836 | } | |
837 | ||
838 | static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen) | |
839 | { | |
840 | return ((uint)sizeof(xfs_attr_leaf_name_local_t) - 1 + (nlen) + (vlen) + | |
841 | XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); | |
842 | } | |
843 | ||
844 | static inline int xfs_attr_leaf_entsize_local_max(int bsize) | |
845 | { | |
846 | return (((bsize) >> 1) + ((bsize) >> 2)); | |
847 | } | |
848 | ||
849 | ||
850 | ||
851 | /* | |
852 | * Remote attribute block format definition | |
853 | * | |
854 | * There is one of these headers per filesystem block in a remote attribute. | |
855 | * This is done to ensure there is a 1:1 mapping between the attribute value | |
856 | * length and the number of blocks needed to store the attribute. This makes the | |
857 | * verification of a buffer a little more complex, but greatly simplifies the | |
858 | * allocation, reading and writing of these attributes as we don't have to guess | |
859 | * the number of blocks needed to store the attribute data. | |
860 | */ | |
861 | #define XFS_ATTR3_RMT_MAGIC 0x5841524d /* XARM */ | |
862 | ||
863 | struct xfs_attr3_rmt_hdr { | |
864 | __be32 rm_magic; | |
865 | __be32 rm_offset; | |
866 | __be32 rm_bytes; | |
867 | __be32 rm_crc; | |
868 | uuid_t rm_uuid; | |
869 | __be64 rm_owner; | |
870 | __be64 rm_blkno; | |
871 | __be64 rm_lsn; | |
872 | }; | |
873 | ||
874 | #define XFS_ATTR3_RMT_CRC_OFF offsetof(struct xfs_attr3_rmt_hdr, rm_crc) | |
875 | ||
876 | #define XFS_ATTR3_RMT_BUF_SPACE(mp, bufsize) \ | |
877 | ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \ | |
878 | sizeof(struct xfs_attr3_rmt_hdr) : 0)) | |
879 | ||
880 | #endif /* __XFS_DA_FORMAT_H__ */ |