2 * Mach Operating System
3 * Copyright (c) 1991,1990 Carnegie Mellon University
6 * Permission to use, copy, modify and distribute this software and its
7 * documentation is hereby granted, provided that both the copyright
8 * notice and this permission notice appear in all copies of the
9 * software, derivative works or modified versions, and any portions
10 * thereof, and that both notices appear in supporting documentation.
12 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
13 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
16 * Carnegie Mellon requests users of this software to return to
18 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
19 * School of Computer Science
20 * Carnegie Mellon University
21 * Pittsburgh PA 15213-3890
23 * any improvements or extensions that they make and grant Carnegie Mellon
24 * the rights to redistribute these changes.
27 * Common definitions for Berkeley Fast File System.
31 * Compatibility definitions for disk IO.
35 * Disk devices do all IO in 512-byte blocks.
40 * Conversion between bytes and disk blocks.
42 #define btodb(byte_offset) ((byte_offset) >> 9)
43 #define dbtob(block_number) ((block_number) << 9)
47 unsigned int val[2]; /* 2 int values make... */
49 quad; /* an 8-byte item */
51 typedef unsigned int mach_time_t; /* an unsigned int */
52 typedef unsigned int mach_daddr_t; /* an unsigned int */
53 typedef unsigned int mach_off_t; /* another unsigned int */
55 typedef unsigned short mach_uid_t;
56 typedef unsigned short mach_gid_t;
57 typedef unsigned int mach_ino_t;
62 * The file system is made out of blocks of at most MAXBSIZE units,
63 * with smaller units (fragments) only in the last direct block.
64 * MAXBSIZE primarily determines the size of buffers in the buffer
65 * pool. It may be made larger without any effect on existing
66 * file systems; however, making it smaller may make some file
67 * systems unmountable.
69 * Note that the disk devices are assumed to have DEV_BSIZE "sectors"
70 * and that fragments must be some multiple of this size.
76 * MAXPATHLEN defines the longest permissible path length
77 * after expanding symbolic links.
79 * MAXSYMLINKS defines the maximum number of symbolic links
80 * that may be expanded in a path name. It should be set
81 * high enough to allow all legitimate uses, but halt infinite
82 * loops reasonably quickly.
85 #define MAXPATHLEN 1024