xref: /linux/fs/squashfs/squashfs_fs.h (revision 1e1159bb97cf4191849b4b03f77ab32977c2ece6)
1 #ifndef SQUASHFS_FS
2 #define SQUASHFS_FS
3 /*
4  * Squashfs
5  *
6  * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
7  * Phillip Lougher <phillip@squashfs.org.uk>
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version 2,
12  * or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
22  *
23  * squashfs_fs.h
24  */
25 
26 #define SQUASHFS_CACHED_FRAGMENTS	CONFIG_SQUASHFS_FRAGMENT_CACHE_SIZE
27 #define SQUASHFS_MAJOR			4
28 #define SQUASHFS_MINOR			0
29 #define SQUASHFS_START			0
30 
31 /* size of metadata (inode and directory) blocks */
32 #define SQUASHFS_METADATA_SIZE		8192
33 
34 /* default size of block device I/O */
35 #ifdef CONFIG_SQUASHFS_4K_DEVBLK_SIZE
36 #define SQUASHFS_DEVBLK_SIZE 4096
37 #else
38 #define SQUASHFS_DEVBLK_SIZE 1024
39 #endif
40 
41 #define SQUASHFS_FILE_MAX_SIZE		1048576
42 #define SQUASHFS_FILE_MAX_LOG		20
43 
44 /* Max length of filename (not 255) */
45 #define SQUASHFS_NAME_LEN		256
46 
47 /* Max value for directory header count*/
48 #define SQUASHFS_DIR_COUNT		256
49 
50 #define SQUASHFS_INVALID_FRAG		(0xffffffffU)
51 #define SQUASHFS_INVALID_XATTR		(0xffffffffU)
52 #define SQUASHFS_INVALID_BLK		(-1LL)
53 
54 /* Filesystem flags */
55 #define SQUASHFS_NOI			0
56 #define SQUASHFS_NOD			1
57 #define SQUASHFS_NOF			3
58 #define SQUASHFS_NO_FRAG		4
59 #define SQUASHFS_ALWAYS_FRAG		5
60 #define SQUASHFS_DUPLICATE		6
61 #define SQUASHFS_EXPORT			7
62 #define SQUASHFS_COMP_OPT		10
63 
64 #define SQUASHFS_BIT(flag, bit)		((flag >> bit) & 1)
65 
66 #define SQUASHFS_UNCOMPRESSED_INODES(flags)	SQUASHFS_BIT(flags, \
67 						SQUASHFS_NOI)
68 
69 #define SQUASHFS_UNCOMPRESSED_DATA(flags)	SQUASHFS_BIT(flags, \
70 						SQUASHFS_NOD)
71 
72 #define SQUASHFS_UNCOMPRESSED_FRAGMENTS(flags)	SQUASHFS_BIT(flags, \
73 						SQUASHFS_NOF)
74 
75 #define SQUASHFS_NO_FRAGMENTS(flags)		SQUASHFS_BIT(flags, \
76 						SQUASHFS_NO_FRAG)
77 
78 #define SQUASHFS_ALWAYS_FRAGMENTS(flags)	SQUASHFS_BIT(flags, \
79 						SQUASHFS_ALWAYS_FRAG)
80 
81 #define SQUASHFS_DUPLICATES(flags)		SQUASHFS_BIT(flags, \
82 						SQUASHFS_DUPLICATE)
83 
84 #define SQUASHFS_EXPORTABLE(flags)		SQUASHFS_BIT(flags, \
85 						SQUASHFS_EXPORT)
86 
87 #define SQUASHFS_COMP_OPTS(flags)		SQUASHFS_BIT(flags, \
88 						SQUASHFS_COMP_OPT)
89 
90 /* Inode types including extended types */
91 #define SQUASHFS_DIR_TYPE		1
92 #define SQUASHFS_REG_TYPE		2
93 #define SQUASHFS_SYMLINK_TYPE		3
94 #define SQUASHFS_BLKDEV_TYPE		4
95 #define SQUASHFS_CHRDEV_TYPE		5
96 #define SQUASHFS_FIFO_TYPE		6
97 #define SQUASHFS_SOCKET_TYPE		7
98 #define SQUASHFS_LDIR_TYPE		8
99 #define SQUASHFS_LREG_TYPE		9
100 #define SQUASHFS_LSYMLINK_TYPE		10
101 #define SQUASHFS_LBLKDEV_TYPE		11
102 #define SQUASHFS_LCHRDEV_TYPE		12
103 #define SQUASHFS_LFIFO_TYPE		13
104 #define SQUASHFS_LSOCKET_TYPE		14
105 
106 /* Max type value stored in directory entry */
107 #define SQUASHFS_MAX_DIR_TYPE		7
108 
109 /* Xattr types */
110 #define SQUASHFS_XATTR_USER             0
111 #define SQUASHFS_XATTR_TRUSTED          1
112 #define SQUASHFS_XATTR_SECURITY         2
113 #define SQUASHFS_XATTR_VALUE_OOL        256
114 #define SQUASHFS_XATTR_PREFIX_MASK      0xff
115 
116 /* Flag whether block is compressed or uncompressed, bit is set if block is
117  * uncompressed */
118 #define SQUASHFS_COMPRESSED_BIT		(1 << 15)
119 
120 #define SQUASHFS_COMPRESSED_SIZE(B)	(((B) & ~SQUASHFS_COMPRESSED_BIT) ? \
121 		(B) & ~SQUASHFS_COMPRESSED_BIT :  SQUASHFS_COMPRESSED_BIT)
122 
123 #define SQUASHFS_COMPRESSED(B)		(!((B) & SQUASHFS_COMPRESSED_BIT))
124 
125 #define SQUASHFS_COMPRESSED_BIT_BLOCK	(1 << 24)
126 
127 #define SQUASHFS_COMPRESSED_SIZE_BLOCK(B)	((B) & \
128 						~SQUASHFS_COMPRESSED_BIT_BLOCK)
129 
130 #define SQUASHFS_COMPRESSED_BLOCK(B)	(!((B) & SQUASHFS_COMPRESSED_BIT_BLOCK))
131 
132 /*
133  * Inode number ops.  Inodes consist of a compressed block number, and an
134  * uncompressed offset within that block
135  */
136 #define SQUASHFS_INODE_BLK(A)		((unsigned int) ((A) >> 16))
137 
138 #define SQUASHFS_INODE_OFFSET(A)	((unsigned int) ((A) & 0xffff))
139 
140 #define SQUASHFS_MKINODE(A, B)		((long long)(((long long) (A)\
141 					<< 16) + (B)))
142 
143 /* fragment and fragment table defines */
144 #define SQUASHFS_FRAGMENT_BYTES(A)	\
145 				((A) * sizeof(struct squashfs_fragment_entry))
146 
147 #define SQUASHFS_FRAGMENT_INDEX(A)	(SQUASHFS_FRAGMENT_BYTES(A) / \
148 					SQUASHFS_METADATA_SIZE)
149 
150 #define SQUASHFS_FRAGMENT_INDEX_OFFSET(A)	(SQUASHFS_FRAGMENT_BYTES(A) % \
151 						SQUASHFS_METADATA_SIZE)
152 
153 #define SQUASHFS_FRAGMENT_INDEXES(A)	((SQUASHFS_FRAGMENT_BYTES(A) + \
154 					SQUASHFS_METADATA_SIZE - 1) / \
155 					SQUASHFS_METADATA_SIZE)
156 
157 #define SQUASHFS_FRAGMENT_INDEX_BYTES(A)	(SQUASHFS_FRAGMENT_INDEXES(A) *\
158 						sizeof(u64))
159 
160 /* inode lookup table defines */
161 #define SQUASHFS_LOOKUP_BYTES(A)	((A) * sizeof(u64))
162 
163 #define SQUASHFS_LOOKUP_BLOCK(A)	(SQUASHFS_LOOKUP_BYTES(A) / \
164 					SQUASHFS_METADATA_SIZE)
165 
166 #define SQUASHFS_LOOKUP_BLOCK_OFFSET(A)	(SQUASHFS_LOOKUP_BYTES(A) % \
167 					SQUASHFS_METADATA_SIZE)
168 
169 #define SQUASHFS_LOOKUP_BLOCKS(A)	((SQUASHFS_LOOKUP_BYTES(A) + \
170 					SQUASHFS_METADATA_SIZE - 1) / \
171 					SQUASHFS_METADATA_SIZE)
172 
173 #define SQUASHFS_LOOKUP_BLOCK_BYTES(A)	(SQUASHFS_LOOKUP_BLOCKS(A) *\
174 					sizeof(u64))
175 
176 /* uid/gid lookup table defines */
177 #define SQUASHFS_ID_BYTES(A)		((A) * sizeof(unsigned int))
178 
179 #define SQUASHFS_ID_BLOCK(A)		(SQUASHFS_ID_BYTES(A) / \
180 					SQUASHFS_METADATA_SIZE)
181 
182 #define SQUASHFS_ID_BLOCK_OFFSET(A)	(SQUASHFS_ID_BYTES(A) % \
183 					SQUASHFS_METADATA_SIZE)
184 
185 #define SQUASHFS_ID_BLOCKS(A)		((SQUASHFS_ID_BYTES(A) + \
186 					SQUASHFS_METADATA_SIZE - 1) / \
187 					SQUASHFS_METADATA_SIZE)
188 
189 #define SQUASHFS_ID_BLOCK_BYTES(A)	(SQUASHFS_ID_BLOCKS(A) *\
190 					sizeof(u64))
191 /* xattr id lookup table defines */
192 #define SQUASHFS_XATTR_BYTES(A)		((A) * sizeof(struct squashfs_xattr_id))
193 
194 #define SQUASHFS_XATTR_BLOCK(A)		(SQUASHFS_XATTR_BYTES(A) / \
195 					SQUASHFS_METADATA_SIZE)
196 
197 #define SQUASHFS_XATTR_BLOCK_OFFSET(A)	(SQUASHFS_XATTR_BYTES(A) % \
198 					SQUASHFS_METADATA_SIZE)
199 
200 #define SQUASHFS_XATTR_BLOCKS(A)	((SQUASHFS_XATTR_BYTES(A) + \
201 					SQUASHFS_METADATA_SIZE - 1) / \
202 					SQUASHFS_METADATA_SIZE)
203 
204 #define SQUASHFS_XATTR_BLOCK_BYTES(A)	(SQUASHFS_XATTR_BLOCKS(A) *\
205 					sizeof(u64))
206 #define SQUASHFS_XATTR_BLK(A)		((unsigned int) ((A) >> 16))
207 
208 #define SQUASHFS_XATTR_OFFSET(A)	((unsigned int) ((A) & 0xffff))
209 
210 /* cached data constants for filesystem */
211 #define SQUASHFS_CACHED_BLKS		8
212 
213 /* meta index cache */
214 #define SQUASHFS_META_INDEXES	(SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
215 #define SQUASHFS_META_ENTRIES	127
216 #define SQUASHFS_META_SLOTS	8
217 
218 struct meta_entry {
219 	u64			data_block;
220 	unsigned int		index_block;
221 	unsigned short		offset;
222 	unsigned short		pad;
223 };
224 
225 struct meta_index {
226 	unsigned int		inode_number;
227 	unsigned int		offset;
228 	unsigned short		entries;
229 	unsigned short		skip;
230 	unsigned short		locked;
231 	unsigned short		pad;
232 	struct meta_entry	meta_entry[SQUASHFS_META_ENTRIES];
233 };
234 
235 
236 /*
237  * definitions for structures on disk
238  */
239 #define ZLIB_COMPRESSION	1
240 #define LZMA_COMPRESSION	2
241 #define LZO_COMPRESSION		3
242 #define XZ_COMPRESSION		4
243 
244 struct squashfs_super_block {
245 	__le32			s_magic;
246 	__le32			inodes;
247 	__le32			mkfs_time;
248 	__le32			block_size;
249 	__le32			fragments;
250 	__le16			compression;
251 	__le16			block_log;
252 	__le16			flags;
253 	__le16			no_ids;
254 	__le16			s_major;
255 	__le16			s_minor;
256 	__le64			root_inode;
257 	__le64			bytes_used;
258 	__le64			id_table_start;
259 	__le64			xattr_id_table_start;
260 	__le64			inode_table_start;
261 	__le64			directory_table_start;
262 	__le64			fragment_table_start;
263 	__le64			lookup_table_start;
264 };
265 
266 struct squashfs_dir_index {
267 	__le32			index;
268 	__le32			start_block;
269 	__le32			size;
270 	unsigned char		name[0];
271 };
272 
273 struct squashfs_base_inode {
274 	__le16			inode_type;
275 	__le16			mode;
276 	__le16			uid;
277 	__le16			guid;
278 	__le32			mtime;
279 	__le32			inode_number;
280 };
281 
282 struct squashfs_ipc_inode {
283 	__le16			inode_type;
284 	__le16			mode;
285 	__le16			uid;
286 	__le16			guid;
287 	__le32			mtime;
288 	__le32			inode_number;
289 	__le32			nlink;
290 };
291 
292 struct squashfs_lipc_inode {
293 	__le16			inode_type;
294 	__le16			mode;
295 	__le16			uid;
296 	__le16			guid;
297 	__le32			mtime;
298 	__le32			inode_number;
299 	__le32			nlink;
300 	__le32			xattr;
301 };
302 
303 struct squashfs_dev_inode {
304 	__le16			inode_type;
305 	__le16			mode;
306 	__le16			uid;
307 	__le16			guid;
308 	__le32			mtime;
309 	__le32			inode_number;
310 	__le32			nlink;
311 	__le32			rdev;
312 };
313 
314 struct squashfs_ldev_inode {
315 	__le16			inode_type;
316 	__le16			mode;
317 	__le16			uid;
318 	__le16			guid;
319 	__le32			mtime;
320 	__le32			inode_number;
321 	__le32			nlink;
322 	__le32			rdev;
323 	__le32			xattr;
324 };
325 
326 struct squashfs_symlink_inode {
327 	__le16			inode_type;
328 	__le16			mode;
329 	__le16			uid;
330 	__le16			guid;
331 	__le32			mtime;
332 	__le32			inode_number;
333 	__le32			nlink;
334 	__le32			symlink_size;
335 	char			symlink[0];
336 };
337 
338 struct squashfs_reg_inode {
339 	__le16			inode_type;
340 	__le16			mode;
341 	__le16			uid;
342 	__le16			guid;
343 	__le32			mtime;
344 	__le32			inode_number;
345 	__le32			start_block;
346 	__le32			fragment;
347 	__le32			offset;
348 	__le32			file_size;
349 	__le16			block_list[0];
350 };
351 
352 struct squashfs_lreg_inode {
353 	__le16			inode_type;
354 	__le16			mode;
355 	__le16			uid;
356 	__le16			guid;
357 	__le32			mtime;
358 	__le32			inode_number;
359 	__le64			start_block;
360 	__le64			file_size;
361 	__le64			sparse;
362 	__le32			nlink;
363 	__le32			fragment;
364 	__le32			offset;
365 	__le32			xattr;
366 	__le16			block_list[0];
367 };
368 
369 struct squashfs_dir_inode {
370 	__le16			inode_type;
371 	__le16			mode;
372 	__le16			uid;
373 	__le16			guid;
374 	__le32			mtime;
375 	__le32			inode_number;
376 	__le32			start_block;
377 	__le32			nlink;
378 	__le16			file_size;
379 	__le16			offset;
380 	__le32			parent_inode;
381 };
382 
383 struct squashfs_ldir_inode {
384 	__le16			inode_type;
385 	__le16			mode;
386 	__le16			uid;
387 	__le16			guid;
388 	__le32			mtime;
389 	__le32			inode_number;
390 	__le32			nlink;
391 	__le32			file_size;
392 	__le32			start_block;
393 	__le32			parent_inode;
394 	__le16			i_count;
395 	__le16			offset;
396 	__le32			xattr;
397 	struct squashfs_dir_index	index[0];
398 };
399 
400 union squashfs_inode {
401 	struct squashfs_base_inode		base;
402 	struct squashfs_dev_inode		dev;
403 	struct squashfs_ldev_inode		ldev;
404 	struct squashfs_symlink_inode		symlink;
405 	struct squashfs_reg_inode		reg;
406 	struct squashfs_lreg_inode		lreg;
407 	struct squashfs_dir_inode		dir;
408 	struct squashfs_ldir_inode		ldir;
409 	struct squashfs_ipc_inode		ipc;
410 	struct squashfs_lipc_inode		lipc;
411 };
412 
413 struct squashfs_dir_entry {
414 	__le16			offset;
415 	__le16			inode_number;
416 	__le16			type;
417 	__le16			size;
418 	char			name[0];
419 };
420 
421 struct squashfs_dir_header {
422 	__le32			count;
423 	__le32			start_block;
424 	__le32			inode_number;
425 };
426 
427 struct squashfs_fragment_entry {
428 	__le64			start_block;
429 	__le32			size;
430 	unsigned int		unused;
431 };
432 
433 struct squashfs_xattr_entry {
434 	__le16			type;
435 	__le16			size;
436 	char			data[0];
437 };
438 
439 struct squashfs_xattr_val {
440 	__le32			vsize;
441 	char			value[0];
442 };
443 
444 struct squashfs_xattr_id {
445 	__le64			xattr;
446 	__le32			count;
447 	__le32			size;
448 };
449 
450 struct squashfs_xattr_id_table {
451 	__le64			xattr_table_start;
452 	__le32			xattr_ids;
453 	__le32			unused;
454 };
455 
456 #endif
457