freebsd-skq/sys/fs/msdosfs/fat.h
jkh 90f90fc347 Update MSDOSFS code using NetBSD's msdosfs as a guide to support
FAT32 partitions.  Unfortunately, we looked around here at
Walnut Creek CDROM for any newer FAT32-supporting versions
of Win95 and we were unsuccessful; only the older stuff here.
So this is untested beyond simply making sure it compiles and
someone with access to an actual FAT32 fs will have
to let us know how well it actually works.
Submitted by:	Dmitrij Tejblum <dima@tejblum.dnttm.rssi.ru>
Obtained from:	NetBSD
1998-02-18 09:28:47 +00:00

109 lines
4.8 KiB
C

/* $Id: fat.h,v 1.6 1997/02/22 09:40:45 peter Exp $ */
/* $NetBSD: fat.h,v 1.12 1997/11/17 15:36:36 ws Exp $ */
/*-
* Copyright (C) 1994, 1997 Wolfgang Solfrank.
* Copyright (C) 1994, 1997 TooLs GmbH.
* All rights reserved.
* Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Written by Paul Popelka (paulp@uts.amdahl.com)
*
* You can do anything you want with this software, just don't say you wrote
* it, and don't remove this notice.
*
* This software is provided "as is".
*
* The author supplies this software to be publicly redistributed on the
* understanding that the author is not responsible for the correct
* functioning of this software in any circumstances and is not liable for
* any damages caused by this software.
*
* October 1992
*/
/*
* Some useful cluster numbers.
*/
#define MSDOSFSROOT 0 /* cluster 0 means the root dir */
#define CLUST_FREE 0 /* cluster 0 also means a free cluster */
#define MSDOSFSFREE CLUST_FREE
#define CLUST_FIRST 2 /* first legal cluster number */
#define CLUST_RSRVD 0xfffffff6 /* reserved cluster range */
#define CLUST_BAD 0xfffffff7 /* a cluster with a defect */
#define CLUST_EOFS 0xfffffff8 /* start of eof cluster range */
#define CLUST_EOFE 0xffffffff /* end of eof cluster range */
#define FAT12_MASK 0x00000fff /* mask for 12 bit cluster numbers */
#define FAT16_MASK 0x0000ffff /* mask for 16 bit cluster numbers */
#define FAT32_MASK 0x0fffffff /* mask for FAT32 cluster numbers */
/*
* MSDOSFS:
* Return true if filesystem uses 12 bit fats. Microsoft Programmer's
* Reference says if the maximum cluster number in a filesystem is greater
* than 4078 ((CLUST_RSRVS - CLUST_FIRST) & FAT12_MASK) then we've got a
* 16 bit fat filesystem. While mounting, the result of this test is stored
* in pm_fatentrysize.
* GEMDOS-flavour (atari):
* If the filesystem is on floppy we've got a 12 bit fat filesystem, otherwise
* 16 bit. We check the d_type field in the disklabel struct while mounting
* and store the result in the pm_fatentrysize. Note that this kind of
* detection gets flakey when mounting a vnd-device.
*/
#define FAT12(pmp) (pmp->pm_fatmask == FAT12_MASK)
#define FAT16(pmp) (pmp->pm_fatmask == FAT16_MASK)
#define FAT32(pmp) (pmp->pm_fatmask == FAT32_MASK)
#define MSDOSFSEOF(pmp, cn) ((((cn) | ~(pmp)->pm_fatmask) & CLUST_EOFS) == CLUST_EOFS)
#ifdef KERNEL
/*
* These are the values for the function argument to the function
* fatentry().
*/
#define FAT_GET 0x0001 /* get a fat entry */
#define FAT_SET 0x0002 /* set a fat entry */
#define FAT_GET_AND_SET (FAT_GET | FAT_SET)
/*
* Flags to extendfile:
*/
#define DE_CLEAR 1 /* Zero out the blocks allocated */
int pcbmap __P((struct denode *dep, u_long findcn, daddr_t *bnp, u_long *cnp, int* sp));
int clusterfree __P((struct msdosfsmount *pmp, u_long cn, u_long *oldcnp));
int clusteralloc __P((struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got));
int fatentry __P((int function, struct msdosfsmount *pmp, u_long cluster, u_long *oldcontents, u_long newcontents));
int freeclusterchain __P((struct msdosfsmount *pmp, u_long startchain));
int extendfile __P((struct denode *dep, u_long count, struct buf **bpp, u_long *ncp, int flags));
void fc_purge __P((struct denode *dep, u_int frcn));
#endif /* KERNEL */