Lines Matching +full:entry +full:- +full:name
1 .. SPDX-License-Identifier: GPL-2.0
4 -----------------
9 that reference the same inode number--these are known as hard links, and
12 associated with a directory file for the particular directory entry that
18 By default, each directory lists its entries in an “almost-linear”
23 entries. The end of each per-block array is signified by reaching the
24 end of the block; the last entry in the block has a record length that
32 The original directory entry format is ``struct ext4_dir_entry``, which
36 .. list-table::
38 :header-rows: 1
40 * - Offset
41 - Size
42 - Name
43 - Description
44 * - 0x0
45 - __le32
46 - inode
47 - Number of the inode that this directory entry points to.
48 * - 0x4
49 - __le16
50 - rec_len
51 - Length of this directory entry. Must be a multiple of 4.
52 * - 0x6
53 - __le16
54 - name_len
55 - Length of the file name.
56 * - 0x8
57 - char
58 - name[EXT4_NAME_LEN]
59 - File name.
62 entry format shortens the name_len field and uses the space for a file
68 .. list-table::
70 :header-rows: 1
72 * - Offset
73 - Size
74 - Name
75 - Description
76 * - 0x0
77 - __le32
78 - inode
79 - Number of the inode that this directory entry points to.
80 * - 0x4
81 - __le16
82 - rec_len
83 - Length of this directory entry.
84 * - 0x6
85 - __u8
86 - name_len
87 - Length of the file name.
88 * - 0x7
89 - __u8
90 - file_type
91 - File type code, see ftype_ table below.
92 * - 0x8
93 - char
94 - name[EXT4_NAME_LEN]
95 - File name.
101 .. list-table::
103 :header-rows: 1
105 * - Value
106 - Description
107 * - 0x0
108 - Unknown.
109 * - 0x1
110 - Regular file.
111 * - 0x2
112 - Directory.
113 * - 0x3
114 - Character device file.
115 * - 0x4
116 - Block device file.
117 * - 0x5
118 - FIFO.
119 * - 0x6
120 - Socket.
121 * - 0x7
122 - Symbolic link.
125 must also include hash information in the directory entry. We append
128 after ``name`` and is included in the size listed by ``rec_len`` If a directory
129 entry uses this extension, it may be up to 271 bytes.
131 .. list-table::
133 :header-rows: 1
135 * - Offset
136 - Size
137 - Name
138 - Description
139 * - 0x0
140 - __le32
141 - hash
142 - The hash of the directory name
143 * - 0x4
144 - __le32
145 - minor_hash
146 - The minor hash of the directory name
151 hold the checksum. The directory entry is 12 bytes long. The inode
153 ignoring an apparently empty directory entry, and the checksum is stored
154 in the place where the name normally goes. The structure is
157 .. list-table::
159 :header-rows: 1
161 * - Offset
162 - Size
163 - Name
164 - Description
165 * - 0x0
166 - __le32
167 - det_reserved_zero1
168 - Inode number, which must be zero.
169 * - 0x4
170 - __le16
171 - det_rec_len
172 - Length of this directory entry, which must be 12.
173 * - 0x6
174 - __u8
175 - det_reserved_zero2
176 - Length of the file name, which must be zero.
177 * - 0x7
178 - __u8
179 - det_reserved_ft
180 - File type, which must be 0xDE.
181 * - 0x8
182 - __le32
183 - det_checksum
184 - Directory leaf block checksum.
188 the entire directory entry block up to (but not including) the fake
189 directory entry.
196 balanced tree keyed off a hash of the directory entry name. If the
199 backwards read-only compatibility with ext2, this tree is actually
202 entry table was signified with an entry pointing to inode 0; this is
203 (ab)used to fool the old linear-scan algorithm into thinking that the
210 the root node contains metadata about the tree and finally a hash->block
212 ``dx_root.info.indirect_levels`` is non-zero then the htree has two
216 minor_hash->block map to find leafe nodes. Leaf nodes contain a linear
220 least-significant bit of the hash (in the interior node map) that gets
224 the desired file name and uses it to find the corresponding block
226 entries that can be searched; otherwise, the minor hash of the file name
239 .. list-table::
241 :header-rows: 1
243 * - Offset
244 - Type
245 - Name
246 - Description
247 * - 0x0
248 - __le32
249 - dot.inode
250 - inode number of this directory.
251 * - 0x4
252 - __le16
253 - dot.rec_len
254 - Length of this record, 12.
255 * - 0x6
256 - u8
257 - dot.name_len
258 - Length of the name, 1.
259 * - 0x7
260 - u8
261 - dot.file_type
262 - File type of this entry, 0x2 (directory) (if the feature flag is set).
263 * - 0x8
264 - char
265 - dot.name[4]
266 - “.\0\0\0”
267 * - 0xC
268 - __le32
269 - dotdot.inode
270 - inode number of parent directory.
271 * - 0x10
272 - __le16
273 - dotdot.rec_len
274 - block_size - 12. The record length is long enough to cover all htree
276 * - 0x12
277 - u8
278 - dotdot.name_len
279 - Length of the name, 2.
280 * - 0x13
281 - u8
282 - dotdot.file_type
283 - File type of this entry, 0x2 (directory) (if the feature flag is set).
284 * - 0x14
285 - char
286 - dotdot_name[4]
287 - “..\0\0”
288 * - 0x18
289 - __le32
290 - struct dx_root_info.reserved_zero
291 - Zero.
292 * - 0x1C
293 - u8
294 - struct dx_root_info.hash_version
295 - Hash type, see dirhash_ table below.
296 * - 0x1D
297 - u8
298 - struct dx_root_info.info_length
299 - Length of the tree information, 0x8.
300 * - 0x1E
301 - u8
302 - struct dx_root_info.indirect_levels
303 - Depth of the htree. Cannot be larger than 3 if the INCOMPAT_LARGEDIR
305 * - 0x1F
306 - u8
307 - struct dx_root_info.unused_flags
308 -
309 * - 0x20
310 - __le16
311 - limit
312 - Maximum number of dx_entries that can follow this header, plus 1 for
314 * - 0x22
315 - __le16
316 - count
317 - Actual number of dx_entries that follow this header, plus 1 for the
319 * - 0x24
320 - __le32
321 - block
322 - The block number (within the directory file) that goes with hash=0.
323 * - 0x28
324 - struct dx_entry
325 - entries[0]
326 - As many 8-byte ``struct dx_entry`` as fits in the rest of the data block.
332 .. list-table::
334 :header-rows: 1
336 * - Value
337 - Description
338 * - 0x0
339 - Legacy.
340 * - 0x1
341 - Half MD4.
342 * - 0x2
343 - Tea.
344 * - 0x3
345 - Legacy, unsigned.
346 * - 0x4
347 - Half MD4, unsigned.
348 * - 0x5
349 - Tea, unsigned.
350 * - 0x6
351 - Siphash.
356 .. list-table::
358 :header-rows: 1
360 * - Offset
361 - Type
362 - Name
363 - Description
364 * - 0x0
365 - __le32
366 - fake.inode
367 - Zero, to make it look like this entry is not in use.
368 * - 0x4
369 - __le16
370 - fake.rec_len
371 - The size of the block, in order to hide all of the dx_node data.
372 * - 0x6
373 - u8
374 - name_len
375 - Zero. There is no name for this “unused” directory entry.
376 * - 0x7
377 - u8
378 - file_type
379 - Zero. There is no file type for this “unused” directory entry.
380 * - 0x8
381 - __le16
382 - limit
383 - Maximum number of dx_entries that can follow this header, plus 1 for
385 * - 0xA
386 - __le16
387 - count
388 - Actual number of dx_entries that follow this header, plus 1 for the
390 * - 0xE
391 - __le32
392 - block
393 - The block number (within the directory file) that goes with the lowest
395 * - 0x12
396 - struct dx_entry
397 - entries[0]
398 - As many 8-byte ``struct dx_entry`` as fits in the rest of the data block.
404 .. list-table::
406 :header-rows: 1
408 * - Offset
409 - Type
410 - Name
411 - Description
412 * - 0x0
413 - __le32
414 - hash
415 - Hash code.
416 * - 0x4
417 - __le32
418 - block
419 - Block number (within the directory file, not filesystem blocks) of the
430 the dx_tail, the user is notified to run e2fsck -D to rebuild the
434 .. list-table::
436 :header-rows: 1
438 * - Offset
439 - Type
440 - Name
441 - Description
442 * - 0x0
443 - u32
444 - dt_reserved
445 - Zero.
446 * - 0x4
447 - __le32
448 - dt_checksum
449 - Checksum of the htree directory block.