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(MAKEFS) 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 98 int pcbmap(struct denode *dep, u_long findcn, daddr_t *bnp, u_long *cnp, int* sp); 99 void clusterfree(struct msdosfsmount *pmp, u_long cn); 100 int clusteralloc(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got); 101 int fatentry(int function, struct msdosfsmount *pmp, u_long cluster, u_long *oldcontents, u_long newcontents); 102 int freeclusterchain(struct msdosfsmount *pmp, u_long startchain); 103 int extendfile(struct denode *dep, u_long count, struct buf **bpp, u_long *ncp, int flags); 104 void fc_purge(struct denode *dep, u_int frcn); 105 int markvoldirty_upgrade(struct msdosfsmount *pmp, bool dirty, bool rw_upgrade); 106 107 static inline int 108 markvoldirty(struct msdosfsmount *pmp, bool dirty) 109 { 110 return (markvoldirty_upgrade(pmp, dirty, false)); 111 } 112 113 #endif /* _KERNEL || MAKEFS */ 114 #endif /* !_FS_MSDOSFS_FAT_H_ */ 115