1 /*
2  *   Copyright (C) International Business Machines Corp., 2000-2003
3  *
4  *   This program is free software;  you can redistribute it and/or modify
5  *   it under the terms of the GNU General Public License as published by
6  *   the Free Software Foundation; either version 2 of the License, or
7  *   (at your option) any later version.
8  *
9  *   This program is distributed in the hope that it will be useful,
10  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
12  *   the GNU General Public License for more details.
13  *
14  *   You should have received a copy of the GNU General Public License
15  *   along with this program;  if not, write to the Free Software
16  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  */
18 #ifndef _H_JFS_FILSYS
19 #define _H_JFS_FILSYS
20 
21 /*
22  *	jfs_filsys.h
23  *
24  * file system (implementation-dependent) constants
25  *
26  * refer to <limits.h> for system wide implementation-dependent constants
27  */
28 
29 /*
30  *	 file system option (superblock flag)
31  */
32 /* mount time flag to disable journaling to disk */
33 #define JFS_NOINTEGRITY 0x00000010
34 
35 /* mount time flags for error handling */
36 #define JFS_ERR_REMOUNT_RO 0x00000002   /* remount read-only */
37 #define JFS_ERR_CONTINUE   0x00000004   /* continue */
38 #define JFS_ERR_PANIC      0x00000008   /* panic */
39 
40 /* platform option (conditional compilation) */
41 #define JFS_AIX		0x80000000	/* AIX support */
42 /*	POSIX name/directory  support */
43 
44 #define JFS_OS2		0x40000000	/* OS/2 support */
45 /*	case-insensitive name/directory support */
46 
47 #define JFS_DFS		0x20000000	/* DCE DFS LFS support */
48 
49 #define JFS_LINUX      	0x10000000	/* Linux support */
50 /*	case-sensitive name/directory support */
51 
52 /* directory option */
53 #define JFS_UNICODE	0x00000001	/* unicode name */
54 
55 /* commit option */
56 #define	JFS_COMMIT	0x00000f00	/* commit option mask */
57 #define	JFS_GROUPCOMMIT	0x00000100	/* group (of 1) commit */
58 #define	JFS_LAZYCOMMIT	0x00000200	/* lazy commit */
59 #define	JFS_TMPFS	0x00000400	/* temporary file system -
60 					 * do not log/commit:
61 					 */
62 
63 /* log logical volume option */
64 #define	JFS_INLINELOG	0x00000800	/* inline log within file system */
65 #define JFS_INLINEMOVE	0x00001000	/* inline log being moved */
66 
67 /* Secondary aggregate inode table */
68 #define JFS_BAD_SAIT	0x00010000	/* current secondary ait is bad */
69 
70 /* sparse regular file support */
71 #define JFS_SPARSE	0x00020000	/* sparse regular file */
72 
73 /* DASD Limits		F226941 */
74 #define JFS_DASD_ENABLED	0x00040000	/* DASD limits enabled */
75 #define	JFS_DASD_PRIME		0x00080000	/* Prime DASD usage on boot */
76 
77 /* big endian flag */
78 #define	JFS_SWAP_BYTES		0x00100000	/* running on big endian computer */
79 
80 /* Directory index */
81 #define JFS_DIR_INDEX		0x00200000	/* Persistant index for */
82 						/* directory entries    */
83 
84 
85 /*
86  *	buffer cache configuration
87  */
88 /* page size */
89 #ifdef PSIZE
90 #undef PSIZE
91 #endif
92 #define	PSIZE		4096	/* page size (in byte) */
93 #define	L2PSIZE		12	/* log2(PSIZE) */
94 #define	POFFSET		4095	/* offset within page */
95 
96 /* buffer page size */
97 #define BPSIZE	PSIZE
98 
99 /*
100  *	fs fundamental size
101  *
102  * PSIZE >= file system block size >= PBSIZE >= DISIZE
103  */
104 #define	PBSIZE		512	/* physical block size (in byte) */
105 #define	L2PBSIZE	9	/* log2(PBSIZE) */
106 
107 #define DISIZE		512	/* on-disk inode size (in byte) */
108 #define L2DISIZE	9	/* log2(DISIZE) */
109 
110 #define IDATASIZE	256	/* inode inline data size */
111 #define	IXATTRSIZE	128	/* inode inline extended attribute size */
112 
113 #define XTPAGE_SIZE     4096
114 #define log2_PAGESIZE     12
115 
116 #define IAG_SIZE        4096
117 #define IAG_EXTENT_SIZE 4096
118 #define	INOSPERIAG	4096	/* number of disk inodes per iag */
119 #define	L2INOSPERIAG	12	/* l2 number of disk inodes per iag */
120 #define INOSPEREXT	32	/* number of disk inode per extent */
121 #define L2INOSPEREXT	5	/* l2 number of disk inode per extent */
122 #define	IXSIZE		(DISIZE * INOSPEREXT)	/* inode extent size */
123 #define	INOSPERPAGE	8	/* number of disk inodes per 4K page */
124 #define	L2INOSPERPAGE	3	/* log2(INOSPERPAGE) */
125 
126 #define	IAGFREELIST_LWM	64
127 
128 #define INODE_EXTENT_SIZE	IXSIZE	/* inode extent size */
129 #define NUM_INODE_PER_EXTENT	INOSPEREXT
130 #define NUM_INODE_PER_IAG	INOSPERIAG
131 
132 #define MINBLOCKSIZE		512
133 #define MAXBLOCKSIZE		4096
134 #define	MAXFILESIZE		((s64)1 << 52)
135 
136 #define JFS_LINK_MAX		65535	/* nlink_t is unsigned short */
137 
138 /* Minimum number of bytes supported for a JFS partition */
139 #define MINJFS			(0x1000000)
140 #define MINJFSTEXT		"16"
141 
142 /*
143  * file system block size -> physical block size
144  */
145 #define LBOFFSET(x)	((x) & (PBSIZE - 1))
146 #define LBNUMBER(x)	((x) >> L2PBSIZE)
147 #define	LBLK2PBLK(sb,b)	((b) << (sb->s_blocksize_bits - L2PBSIZE))
148 #define	PBLK2LBLK(sb,b)	((b) >> (sb->s_blocksize_bits - L2PBSIZE))
149 /* size in byte -> last page number */
150 #define	SIZE2PN(size)	( ((s64)((size) - 1)) >> (L2PSIZE) )
151 /* size in byte -> last file system block number */
152 #define	SIZE2BN(size, l2bsize) ( ((s64)((size) - 1)) >> (l2bsize) )
153 
154 /*
155  * fixed physical block address (physical block size = 512 byte)
156  *
157  * NOTE: since we can't guarantee a physical block size of 512 bytes the use of
158  *	 these macros should be removed and the byte offset macros used instead.
159  */
160 #define SUPER1_B	64	/* primary superblock */
161 #define	AIMAP_B		(SUPER1_B + 8)	/* 1st extent of aggregate inode map */
162 #define	AITBL_B		(AIMAP_B + 16)	/*
163 					 * 1st extent of aggregate inode table
164 					 */
165 #define	SUPER2_B	(AITBL_B + 32)	/* 2ndary superblock pbn */
166 #define	BMAP_B		(SUPER2_B + 8)	/* block allocation map */
167 
168 /*
169  * SIZE_OF_SUPER defines the total amount of space reserved on disk for the
170  * superblock.  This is not the same as the superblock structure, since all of
171  * this space is not currently being used.
172  */
173 #define SIZE_OF_SUPER	PSIZE
174 
175 /*
176  * SIZE_OF_AG_TABLE defines the amount of space reserved to hold the AG table
177  */
178 #define SIZE_OF_AG_TABLE	PSIZE
179 
180 /*
181  * SIZE_OF_MAP_PAGE defines the amount of disk space reserved for each page of
182  * the inode allocation map (to hold iag)
183  */
184 #define SIZE_OF_MAP_PAGE	PSIZE
185 
186 /*
187  * fixed byte offset address
188  */
189 #define SUPER1_OFF	0x8000	/* primary superblock */
190 #define AIMAP_OFF	(SUPER1_OFF + SIZE_OF_SUPER)
191 					/*
192 					 * Control page of aggregate inode map
193 					 * followed by 1st extent of map
194 					 */
195 #define AITBL_OFF	(AIMAP_OFF + (SIZE_OF_MAP_PAGE << 1))
196 					/*
197 					 * 1st extent of aggregate inode table
198 					 */
199 #define SUPER2_OFF	(AITBL_OFF + INODE_EXTENT_SIZE)
200 					/*
201 					 * secondary superblock
202 					 */
203 #define BMAP_OFF	(SUPER2_OFF + SIZE_OF_SUPER)
204 					/*
205 					 * block allocation map
206 					 */
207 
208 /*
209  * The following macro is used to indicate the number of reserved disk blocks at
210  * the front of an aggregate, in terms of physical blocks.  This value is
211  * currently defined to be 32K.  This turns out to be the same as the primary
212  * superblock's address, since it directly follows the reserved blocks.
213  */
214 #define AGGR_RSVD_BLOCKS	SUPER1_B
215 
216 /*
217  * The following macro is used to indicate the number of reserved bytes at the
218  * front of an aggregate.  This value is currently defined to be 32K.  This
219  * turns out to be the same as the primary superblock's byte offset, since it
220  * directly follows the reserved blocks.
221  */
222 #define AGGR_RSVD_BYTES	SUPER1_OFF
223 
224 /*
225  * The following macro defines the byte offset for the first inode extent in
226  * the aggregate inode table.  This allows us to find the self inode to find the
227  * rest of the table.  Currently this value is 44K.
228  */
229 #define AGGR_INODE_TABLE_START	AITBL_OFF
230 
231 /*
232  *	fixed reserved inode number
233  */
234 /* aggregate inode */
235 #define AGGR_RESERVED_I	0	/* aggregate inode (reserved) */
236 #define	AGGREGATE_I	1	/* aggregate inode map inode */
237 #define	BMAP_I		2	/* aggregate block allocation map inode */
238 #define	LOG_I		3	/* aggregate inline log inode */
239 #define BADBLOCK_I	4	/* aggregate bad block inode */
240 #define	FILESYSTEM_I	16	/* 1st/only fileset inode in ait:
241 				 * fileset inode map inode
242 				 */
243 
244 /* per fileset inode */
245 #define FILESET_RSVD_I	0	/* fileset inode (reserved) */
246 #define FILESET_EXT_I	1	/* fileset inode extension */
247 #define	ROOT_I		2	/* fileset root inode */
248 #define ACL_I		3	/* fileset ACL inode */
249 
250 #define FILESET_OBJECT_I 4	/* the first fileset inode available for a file
251 				 * or directory or link...
252 				 */
253 #define FIRST_FILESET_INO 16	/* the first aggregate inode which describes
254 				 * an inode.  (To fsck this is also the first
255 				 * inode in part 2 of the agg inode table.)
256 				 */
257 
258 /*
259  *	directory configuration
260  */
261 #define JFS_NAME_MAX	255
262 #define JFS_PATH_MAX	BPSIZE
263 
264 
265 /*
266  *	file system state (superblock state)
267  */
268 #define FM_CLEAN 0x00000000	/* file system is unmounted and clean */
269 #define FM_MOUNT 0x00000001	/* file system is mounted cleanly */
270 #define FM_DIRTY 0x00000002	/* file system was not unmounted and clean
271 				 * when mounted or
272 				 * commit failure occurred while being mounted:
273 				 * fsck() must be run to repair
274 				 */
275 #define	FM_LOGREDO 0x00000004	/* log based recovery (logredo()) failed:
276 				 * fsck() must be run to repair
277 				 */
278 #define	FM_EXTENDFS 0x00000008	/* file system extendfs() in progress */
279 
280 #endif				/* _H_JFS_FILSYS */
281