1/* $NetBSD: fat.h,v 1.12 1997/11/17 15:36:36 ws Exp $ */
2
3/*-
4 * SPDX-License-Identifier: BSD-4-Clause
5 *
6 * Copyright (C) 1994, 1997 Wolfgang Solfrank.
7 * Copyright (C) 1994, 1997 TooLs GmbH.
8 * All rights reserved.
9 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by TooLs GmbH.
22 * 4. The name of TooLs GmbH may not be used to endorse or promote products
23 * derived from this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
29 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
30 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
31 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
32 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
33 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
34 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 */
36/*-
37 * Written by Paul Popelka (paulp@uts.amdahl.com)
38 *
39 * You can do anything you want with this software, just don't say you wrote
40 * it, and don't remove this notice.
41 *
42 * This software is provided "as is".
43 *
44 * The author supplies this software to be publicly redistributed on the
45 * understanding that the author is not responsible for the correct
46 * functioning of this software in any circumstances and is not liable for
47 * any damages caused by this software.
48 *
49 * October 1992
50 */
51
52#ifndef _FS_MSDOSFS_FAT_H_
53#define _FS_MSDOSFS_FAT_H_
54/*
55 * Some useful cluster numbers.
56 */
57#define MSDOSFSROOT 0 /* cluster 0 means the root dir */
58#define CLUST_FREE 0 /* cluster 0 also means a free cluster */
59#define MSDOSFSFREE CLUST_FREE
60#define CLUST_FIRST 2 /* first legal cluster number */
61#define CLUST_RSRVD 0xfffffff6 /* reserved cluster range */
62#define CLUST_BAD 0xfffffff7 /* a cluster with a defect */
63#define CLUST_EOFS 0xfffffff8 /* start of eof cluster range */
64#define CLUST_EOFE 0xffffffff /* end of eof cluster range */
65
66#define FAT12_MASK 0x00000fff /* mask for 12 bit cluster numbers */
67#define FAT16_MASK 0x0000ffff /* mask for 16 bit cluster numbers */
68#define FAT32_MASK 0x0fffffff /* mask for FAT32 cluster numbers */
69
70/*
71 * MSDOSFS:
72 * Return true if filesystem uses 12 bit FATs. Microsoft Programmer's
73 * Reference says if the maximum cluster number in a filesystem is greater
74 * than 4084 ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK) then we've got a
75 * 16 bit FAT filesystem. While mounting, the result of this test is stored
76 * in pm_fatentrysize.
77 */
78#define FAT12(pmp) (pmp->pm_fatmask == FAT12_MASK)
79#define FAT16(pmp) (pmp->pm_fatmask == FAT16_MASK)
80#define FAT32(pmp) (pmp->pm_fatmask == FAT32_MASK)
81
82#define MSDOSFSEOF(pmp, cn) ((((cn) | ~(pmp)->pm_fatmask) & CLUST_EOFS) == CLUST_EOFS)
83
84#if defined (_KERNEL) || defined(_WANT_MSDOSFS_INTERNALS)
85/*
86 * These are the values for the function argument to the function
87 * fatentry().
88 */
89#define FAT_GET 0x0001 /* get a FAT entry */
90#define FAT_SET 0x0002 /* set a FAT entry */
91#define FAT_GET_AND_SET (FAT_GET | FAT_SET)
92
93/*
94 * Flags to extendfile:
95 */
96#define DE_CLEAR 1 /* Zero out the blocks allocated */
97
98int pcbmap(struct denode *dep, u_long findcn, daddr_t *bnp, u_long *cnp, int* sp);
99void clusterfree(struct msdosfsmount *pmp, u_long cn);
100int clusteralloc(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got);
101int fatentry(int function, struct msdosfsmount *pmp, u_long cluster, u_long *oldcontents, u_long newcontents);
102int freeclusterchain(struct msdosfsmount *pmp, u_long startchain);
103int extendfile(struct denode *dep, u_long count, struct buf **bpp, u_long *ncp, int flags);
104void fc_purge(struct denode *dep, u_int frcn);
105int markvoldirty_upgrade(struct msdosfsmount *pmp, bool dirty, bool rw_upgrade);
106
107static inline int
108markvoldirty(struct msdosfsmount *pmp, bool dirty)
109{
110 return (markvoldirty_upgrade(pmp, dirty, false));
111}
112
113#endif /* _KERNEL || _WANT_MSDOSFS_INTERNALS */
114#endif /* !_FS_MSDOSFS_FAT_H_ */