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/* $FreeBSD$ */
/* $NetBSD: msdosfsmount.h,v 1.7 1994/08/21 18:44:17 ws Exp $ */
/*-
* Copyright (C) 1994 Wolfgang Solfrank.
* Copyright (C) 1994 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
*/
/*
* Layout of the mount control block for a msdos file system.
*/
struct msdosfsmount {
struct mount *pm_mountp;/* vfs mount struct for this fs */
dev_t pm_dev; /* block special device mounted */
uid_t pm_mounter; /* uid of the user who mounted the FS */
uid_t pm_uid; /* uid to set as owner of the files */
gid_t pm_gid; /* gid to set as owner of the files */
mode_t pm_mask; /* mask to and with file protection bits */
struct vnode *pm_devvp; /* vnode for block device mntd */
struct bpb50 pm_bpb; /* BIOS parameter blk for this fs */
u_long pm_fatblk; /* block # of first FAT */
u_long pm_rootdirblk; /* block # of root directory */
u_long pm_rootdirsize; /* size in blocks (not clusters) */
u_long pm_firstcluster; /* block number of first cluster */
u_long pm_nmbrofclusters; /* # of clusters in filesystem */
u_long pm_maxcluster; /* maximum cluster number */
u_long pm_freeclustercount; /* number of free clusters */
u_long pm_bnshift; /* shift file offset right this amount to get a block number */
u_long pm_brbomask; /* and a file offset with this mask to get block rel offset */
u_long pm_cnshift; /* shift file offset right this amount to get a cluster number */
u_long pm_crbomask; /* and a file offset with this mask to get cluster rel offset */
u_long pm_bpcluster; /* bytes per cluster */
u_long pm_depclust; /* directory entries per cluster */
u_long pm_fmod; /* ~0 if fs is modified, this can rollover to 0 */
u_long pm_fatblocksize; /* size of fat blocks in bytes */
u_long pm_fatblocksec; /* size of fat blocks in sectors */
u_long pm_fatsize; /* size of fat in bytes */
u_int *pm_inusemap; /* ptr to bitmap of in-use clusters */
char pm_ronly; /* read only if non-zero */
char pm_waitonfat; /* wait for writes of the fat to complete, when 0 use bdwrite, else use bwrite */
struct netexport pm_export; /* export information */
};
/* Number of bits in one pm_inusemap item: */
#define N_INUSEBITS (8 * sizeof(u_int))
/*
* How to compute pm_cnshift and pm_crbomask.
*
* pm_crbomask = (pm_SectPerClust * pm_BytesPerSect) - 1
* if (bytesperclust == * 0)
* return EBADBLKSZ;
* bit = 1;
* for (i = 0; i < 32; i++) {
* if (bit & bytesperclust) {
* if (bit ^ bytesperclust)
* return EBADBLKSZ;
* pm_cnshift = * i;
* break;
* }
* bit <<= 1;
* }
*/
/*
* Shorthand for fields in the bpb contained in the msdosfsmount structure.
*/
#define pm_BytesPerSec pm_bpb.bpbBytesPerSec
#define pm_SectPerClust pm_bpb.bpbSecPerClust
#define pm_ResSectors pm_bpb.bpbResSectors
#define pm_FATs pm_bpb.bpbFATs
#define pm_RootDirEnts pm_bpb.bpbRootDirEnts
#define pm_Sectors pm_bpb.bpbSectors
#define pm_Media pm_bpb.bpbMedia
#define pm_FATsecs pm_bpb.bpbFATsecs
#define pm_SecPerTrack pm_bpb.bpbSecPerTrack
#define pm_Heads pm_bpb.bpbHeads
#define pm_HiddenSects pm_bpb.bpbHiddenSecs
#define pm_HugeSectors pm_bpb.bpbHugeSectors
/*
* Map a cluster number into a filesystem relative block number.
*/
#define cntobn(pmp, cn) \
((((cn)-CLUST_FIRST) * (pmp)->pm_SectPerClust) + (pmp)->pm_firstcluster)
/*
* Map a filesystem relative block number back into a cluster number.
*/
#define bntocn(pmp, bn) \
((((bn) - pmp->pm_firstcluster)/ (pmp)->pm_SectPerClust) + CLUST_FIRST)
/*
* Calculate block number for directory entry in root dir, offset dirofs
*/
#define roottobn(pmp, dirofs) \
(((dirofs) / (pmp)->pm_depclust) * (pmp)->pm_SectPerClust \
+ (pmp)->pm_rootdirblk)
/*
* Calculate block number for directory entry at cluster dirclu, offset
* dirofs
*/
#define detobn(pmp, dirclu, dirofs) \
((dirclu) == MSDOSFSROOT \
? roottobn((pmp), (dirofs)) \
: cntobn((pmp), (dirclu)))
/*
* Convert pointer to buffer -> pointer to direntry
*/
#define bptoep(pmp, bp, dirofs) \
((struct direntry *)((bp)->b_data) \
+ (dirofs) % (pmp)->pm_depclust)
/*
* Convert filesize to block number
*/
#define de_blk(pmp, off) \
((off) >> (pmp)->pm_cnshift)
/*
* Clusters required to hold size bytes
*/
#define de_clcount(pmp, size) \
(((size) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift)
int msdosfs_init __P((void));
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