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@lougher.demon.co.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_MAGIC			0x73717368
30#define SQUASHFS_START			0
31
32/* size of metadata (inode and directory) blocks */
33#define SQUASHFS_METADATA_SIZE		8192
34#define SQUASHFS_METADATA_LOG		13
35
36/* default size of data blocks */
37#define SQUASHFS_FILE_SIZE		131072
38#define SQUASHFS_FILE_LOG		17
39
40#define SQUASHFS_FILE_MAX_SIZE		1048576
41
42/* Max number of uids and gids */
43#define SQUASHFS_IDS			65536
44
45/* Max length of filename (not 255) */
46#define SQUASHFS_NAME_LEN		256
47
48#define SQUASHFS_INVALID_FRAG		(0xffffffffU)
49#define SQUASHFS_INVALID_BLK		(-1LL)
50
51/* Filesystem flags */
52#define SQUASHFS_NOI			0
53#define SQUASHFS_NOD			1
54#define SQUASHFS_NOF			3
55#define SQUASHFS_NO_FRAG		4
56#define SQUASHFS_ALWAYS_FRAG		5
57#define SQUASHFS_DUPLICATE		6
58#define SQUASHFS_EXPORT			7
59
60#define SQUASHFS_BIT(flag, bit)		((flag >> bit) & 1)
61
62#define SQUASHFS_UNCOMPRESSED_INODES(flags)	SQUASHFS_BIT(flags, \
63						SQUASHFS_NOI)
64
65#define SQUASHFS_UNCOMPRESSED_DATA(flags)	SQUASHFS_BIT(flags, \
66						SQUASHFS_NOD)
67
68#define SQUASHFS_UNCOMPRESSED_FRAGMENTS(flags)	SQUASHFS_BIT(flags, \
69						SQUASHFS_NOF)
70
71#define SQUASHFS_NO_FRAGMENTS(flags)		SQUASHFS_BIT(flags, \
72						SQUASHFS_NO_FRAG)
73
74#define SQUASHFS_ALWAYS_FRAGMENTS(flags)	SQUASHFS_BIT(flags, \
75						SQUASHFS_ALWAYS_FRAG)
76
77#define SQUASHFS_DUPLICATES(flags)		SQUASHFS_BIT(flags, \
78						SQUASHFS_DUPLICATE)
79
80#define SQUASHFS_EXPORTABLE(flags)		SQUASHFS_BIT(flags, \
81						SQUASHFS_EXPORT)
82
83/* Max number of types and file types */
84#define SQUASHFS_DIR_TYPE		1
85#define SQUASHFS_REG_TYPE		2
86#define SQUASHFS_SYMLINK_TYPE		3
87#define SQUASHFS_BLKDEV_TYPE		4
88#define SQUASHFS_CHRDEV_TYPE		5
89#define SQUASHFS_FIFO_TYPE		6
90#define SQUASHFS_SOCKET_TYPE		7
91#define SQUASHFS_LDIR_TYPE		8
92#define SQUASHFS_LREG_TYPE		9
93#define SQUASHFS_LSYMLINK_TYPE		10
94#define SQUASHFS_LBLKDEV_TYPE		11
95#define SQUASHFS_LCHRDEV_TYPE		12
96#define SQUASHFS_LFIFO_TYPE		13
97#define SQUASHFS_LSOCKET_TYPE		14
98
99/* Flag whether block is compressed or uncompressed, bit is set if block is
100 * uncompressed */
101#define SQUASHFS_COMPRESSED_BIT		(1 << 15)
102
103#define SQUASHFS_COMPRESSED_SIZE(B)	(((B) & ~SQUASHFS_COMPRESSED_BIT) ? \
104		(B) & ~SQUASHFS_COMPRESSED_BIT :  SQUASHFS_COMPRESSED_BIT)
105
106#define SQUASHFS_COMPRESSED(B)		(!((B) & SQUASHFS_COMPRESSED_BIT))
107
108#define SQUASHFS_COMPRESSED_BIT_BLOCK	(1 << 24)
109
110#define SQUASHFS_COMPRESSED_SIZE_BLOCK(B)	((B) & \
111						~SQUASHFS_COMPRESSED_BIT_BLOCK)
112
113#define SQUASHFS_COMPRESSED_BLOCK(B)	(!((B) & SQUASHFS_COMPRESSED_BIT_BLOCK))
114
115/*
116 * Inode number ops.  Inodes consist of a compressed block number, and an
117 * uncompressed offset within that block
118 */
119#define SQUASHFS_INODE_BLK(A)		((unsigned int) ((A) >> 16))
120
121#define SQUASHFS_INODE_OFFSET(A)	((unsigned int) ((A) & 0xffff))
122
123#define SQUASHFS_MKINODE(A, B)		((long long)(((long long) (A)\
124					<< 16) + (B)))
125
126/* Translate between VFS mode and squashfs mode */
127#define SQUASHFS_MODE(A)		((A) & 0xfff)
128
129/* fragment and fragment table defines */
130#define SQUASHFS_FRAGMENT_BYTES(A)	\
131				((A) * sizeof(struct squashfs_fragment_entry))
132
133#define SQUASHFS_FRAGMENT_INDEX(A)	(SQUASHFS_FRAGMENT_BYTES(A) / \
134					SQUASHFS_METADATA_SIZE)
135
136#define SQUASHFS_FRAGMENT_INDEX_OFFSET(A)	(SQUASHFS_FRAGMENT_BYTES(A) % \
137						SQUASHFS_METADATA_SIZE)
138
139#define SQUASHFS_FRAGMENT_INDEXES(A)	((SQUASHFS_FRAGMENT_BYTES(A) + \
140					SQUASHFS_METADATA_SIZE - 1) / \
141					SQUASHFS_METADATA_SIZE)
142
143#define SQUASHFS_FRAGMENT_INDEX_BYTES(A)	(SQUASHFS_FRAGMENT_INDEXES(A) *\
144						sizeof(long long))
145
146/* inode lookup table defines */
147#define SQUASHFS_LOOKUP_BYTES(A)	((A) * sizeof(long long))
148
149#define SQUASHFS_LOOKUP_BLOCK(A)	(SQUASHFS_LOOKUP_BYTES(A) / \
150					SQUASHFS_METADATA_SIZE)
151
152#define SQUASHFS_LOOKUP_BLOCK_OFFSET(A)	(SQUASHFS_LOOKUP_BYTES(A) % \
153					SQUASHFS_METADATA_SIZE)
154
155#define SQUASHFS_LOOKUP_BLOCKS(A)	((SQUASHFS_LOOKUP_BYTES(A) + \
156					SQUASHFS_METADATA_SIZE - 1) / \
157					SQUASHFS_METADATA_SIZE)
158
159#define SQUASHFS_LOOKUP_BLOCK_BYTES(A)	(SQUASHFS_LOOKUP_BLOCKS(A) *\
160					sizeof(long long))
161
162/* uid/gid lookup table defines */
163#define SQUASHFS_ID_BYTES(A)		((A) * sizeof(unsigned int))
164
165#define SQUASHFS_ID_BLOCK(A)		(SQUASHFS_ID_BYTES(A) / \
166					SQUASHFS_METADATA_SIZE)
167
168#define SQUASHFS_ID_BLOCK_OFFSET(A)	(SQUASHFS_ID_BYTES(A) % \
169					SQUASHFS_METADATA_SIZE)
170
171#define SQUASHFS_ID_BLOCKS(A)		((SQUASHFS_ID_BYTES(A) + \
172					SQUASHFS_METADATA_SIZE - 1) / \
173					SQUASHFS_METADATA_SIZE)
174
175#define SQUASHFS_ID_BLOCK_BYTES(A)	(SQUASHFS_ID_BLOCKS(A) *\
176					sizeof(long long))
177
178/* cached data constants for filesystem */
179#define SQUASHFS_CACHED_BLKS		8
180
181#define SQUASHFS_MAX_FILE_SIZE_LOG	64
182
183#define SQUASHFS_MAX_FILE_SIZE		(1LL << \
184					(SQUASHFS_MAX_FILE_SIZE_LOG - 2))
185
186#define SQUASHFS_MARKER_BYTE		0xff
187
188/* meta index cache */
189#define SQUASHFS_META_INDEXES	(SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
190#define SQUASHFS_META_ENTRIES	127
191#define SQUASHFS_META_SLOTS	8
192
193struct meta_entry {
194	long long		data_block;
195	unsigned int		index_block;
196	unsigned short		offset;
197	unsigned short		pad;
198};
199
200struct meta_index {
201	unsigned int		inode_number;
202	unsigned int		offset;
203	unsigned short		entries;
204	unsigned short		skip;
205	unsigned short		locked;
206	unsigned short		pad;
207	struct meta_entry	meta_entry[SQUASHFS_META_ENTRIES];
208};
209
210
211/*
212 * definitions for structures on disk
213 */
214#define ZLIB_COMPRESSION	 1
215
216struct squashfs_super_block {
217	__le32			s_magic;
218	__le32			inodes;
219	__le32			mkfs_time;
220	__le32			block_size;
221	__le32			fragments;
222	__le16			compression;
223	__le16			block_log;
224	__le16			flags;
225	__le16			no_ids;
226	__le16			s_major;
227	__le16			s_minor;
228	__le64			root_inode;
229	__le64			bytes_used;
230	__le64			id_table_start;
231	__le64			xattr_table_start;
232	__le64			inode_table_start;
233	__le64			directory_table_start;
234	__le64			fragment_table_start;
235	__le64			lookup_table_start;
236};
237
238struct squashfs_dir_index {
239	__le32			index;
240	__le32			start_block;
241	__le32			size;
242	unsigned char		name[0];
243};
244
245struct squashfs_base_inode {
246	__le16			inode_type;
247	__le16			mode;
248	__le16			uid;
249	__le16			guid;
250	__le32			mtime;
251	__le32	 		inode_number;
252};
253
254struct squashfs_ipc_inode {
255	__le16			inode_type;
256	__le16			mode;
257	__le16			uid;
258	__le16			guid;
259	__le32			mtime;
260	__le32	 		inode_number;
261	__le32			nlink;
262};
263
264struct squashfs_dev_inode {
265	__le16			inode_type;
266	__le16			mode;
267	__le16			uid;
268	__le16			guid;
269	__le32			mtime;
270	__le32	 		inode_number;
271	__le32			nlink;
272	__le32			rdev;
273};
274
275struct squashfs_symlink_inode {
276	__le16			inode_type;
277	__le16			mode;
278	__le16			uid;
279	__le16			guid;
280	__le32			mtime;
281	__le32	 		inode_number;
282	__le32			nlink;
283	__le32			symlink_size;
284	char			symlink[0];
285};
286
287struct squashfs_reg_inode {
288	__le16			inode_type;
289	__le16			mode;
290	__le16			uid;
291	__le16			guid;
292	__le32			mtime;
293	__le32	 		inode_number;
294	__le32			start_block;
295	__le32			fragment;
296	__le32			offset;
297	__le32			file_size;
298	__le16			block_list[0];
299};
300
301struct squashfs_lreg_inode {
302	__le16			inode_type;
303	__le16			mode;
304	__le16			uid;
305	__le16			guid;
306	__le32			mtime;
307	__le32	 		inode_number;
308	__le64			start_block;
309	__le64			file_size;
310	__le64			sparse;
311	__le32			nlink;
312	__le32			fragment;
313	__le32			offset;
314	__le32			xattr;
315	__le16			block_list[0];
316};
317
318struct squashfs_dir_inode {
319	__le16			inode_type;
320	__le16			mode;
321	__le16			uid;
322	__le16			guid;
323	__le32			mtime;
324	__le32	 		inode_number;
325	__le32			start_block;
326	__le32			nlink;
327	__le16			file_size;
328	__le16			offset;
329	__le32			parent_inode;
330};
331
332struct squashfs_ldir_inode {
333	__le16			inode_type;
334	__le16			mode;
335	__le16			uid;
336	__le16			guid;
337	__le32			mtime;
338	__le32	 		inode_number;
339	__le32			nlink;
340	__le32			file_size;
341	__le32			start_block;
342	__le32			parent_inode;
343	__le16			i_count;
344	__le16			offset;
345	__le32			xattr;
346	struct squashfs_dir_index	index[0];
347};
348
349union squashfs_inode {
350	struct squashfs_base_inode		base;
351	struct squashfs_dev_inode		dev;
352	struct squashfs_symlink_inode		symlink;
353	struct squashfs_reg_inode		reg;
354	struct squashfs_lreg_inode		lreg;
355	struct squashfs_dir_inode		dir;
356	struct squashfs_ldir_inode		ldir;
357	struct squashfs_ipc_inode		ipc;
358};
359
360struct squashfs_dir_entry {
361	__le16			offset;
362	__le16			inode_number;
363	__le16			type;
364	__le16			size;
365	char			name[0];
366};
367
368struct squashfs_dir_header {
369	__le32			count;
370	__le32			start_block;
371	__le32			inode_number;
372};
373
374struct squashfs_fragment_entry {
375	__le64			start_block;
376	__le32			size;
377	unsigned int		unused;
378};
379
380#endif
381