/*      $NetBSD: msdosfsmount.h,v 1.21 2016/01/30 09:59:27 mlelstv Exp $        */

/*-
* Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
* Copyright (C) 1994, 1995, 1997 TooLs GmbH.
* All rights reserved.
* Original code by Paul Popelka ([email protected]) (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 ([email protected])
*
* 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
*/

#ifndef _MSDOSFS_MSDOSFSMOUNT_H_
#define _MSDOSFS_MSDOSFSMOUNT_H_

#ifndef MAKEFS
/*
*  Arguments to mount MSDOS filesystems.
*/
struct msdosfs_args {
       char    *fspec;         /* blocks special holding the fs to mount */
       struct  export_args30 _pad1; /* compat with old userland tools */
       uid_t   uid;            /* uid that owns msdosfs files */
       gid_t   gid;            /* gid that owns msdosfs files */
       mode_t  mask;           /* mask to be applied for msdosfs perms */
       int     flags;          /* see below */

       /* Following items added after versioning support */
       int     version;        /* version of the struct */
#define MSDOSFSMNT_VERSION      3
       mode_t  dirmask;        /* v2: mask to be applied for msdosfs perms */
       int     gmtoff;         /* v3: offset from UTC in seconds */
};
#endif

/*
* Msdosfs mount options:
*/
#define MSDOSFSMNT_SHORTNAME    1       /* Force old DOS short names only */
#define MSDOSFSMNT_LONGNAME     2       /* Force Win'95 long names */
#define MSDOSFSMNT_NOWIN95      4       /* Completely ignore Win95 entries */
#define MSDOSFSMNT_GEMDOSFS     8       /* This is a GEMDOS-flavour */
#define MSDOSFSMNT_VERSIONED    16      /* Struct is versioned */
#define MSDOSFSMNT_UTF8         32      /* Use UTF8 filenames */

/* All flags above: */
#define MSDOSFSMNT_MNTOPT \
       (MSDOSFSMNT_SHORTNAME|MSDOSFSMNT_LONGNAME|MSDOSFSMNT_NOWIN95 \
        |MSDOSFSMNT_GEMDOSFS|MSDOSFSMNT_VERSIONED|MSDOSFSMNT_UTF8)

#define MSDOSFSMNT_RONLY        0x80000000      /* mounted read-only    */
#define MSDOSFSMNT_WAITONFAT    0x40000000      /* mounted synchronous  */
#define MSDOSFS_FATMIRROR       0x20000000      /* FAT is mirrored */

#define MSDOSFSMNT_BITS "\177\20" \
   "b\00shortname\0b\01longname\0b\02nowin95\0b\03gemdosfs\0b\04mntversioned\0" \
   "b\05utf8\0b\037ronly\0b\036waitonfat\0b\035fatmirror\0"

#ifdef _KERNEL
#include <sys/mallocvar.h>
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_MSDOSFSMNT);
MALLOC_DECLARE(M_MSDOSFSTMP);
#endif
#endif

#if defined(_KERNEL) || defined(MAKEFS)
/*
* Layout of the mount control block for a MSDOSFS 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_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
                                  for files */
       mode_t pm_dirmask;      /* mask to and with file protection bits
                                  for directories */
       int pm_gmtoff;          /* offset from UTC in seconds */
       struct vnode *pm_devvp; /* vnode for block device mntd */
       struct bpb50 pm_bpb;    /* BIOS parameter blk for this fs */
       u_long pm_FATsecs;      /* actual number of FAT sectors */
       u_long pm_fatblk;       /* sector # of first FAT */
       u_long pm_rootdirblk;   /* sector # (cluster # for FAT32) of root directory number */
       u_long pm_rootdirsize;  /* size in sectors (not clusters) */
       u_long pm_firstcluster; /* sector 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_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_bnshift;      /* shift file offset right this amount to get a sector number */
       u_long pm_bpcluster;    /* bytes 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_long pm_fatmask;      /* mask to use for FAT numbers */
       u_long pm_fsinfo;       /* fsinfo block number */
       u_long pm_nxtfree;      /* next free cluster in fsinfo block */
       u_int pm_fatmult;       /* these 2 values are used in FAT */
       u_int pm_fatdiv;        /*      offset computation */
       u_int pm_curfat;        /* current FAT for FAT32 (0 otherwise) */
       u_int *pm_inusemap;     /* ptr to bitmap of in-use clusters */
       u_int pm_flags;         /* see below */
};
/* Byte offset in FAT on filesystem pmp, cluster cn */
#define FATOFS(pmp, cn) ((cn) * (pmp)->pm_fatmult / (pmp)->pm_fatdiv)

#define VFSTOMSDOSFS(mp)        ((struct msdosfsmount *)mp->mnt_data)

/* Number of bits in one pm_inusemap item: */
#define N_INUSEBITS     (8 * sizeof(u_int))

/*
* Shorthand for fields in the bpb contained in the msdosfsmount structure.
*/
#define pm_BytesPerSec  pm_bpb.bpbBytesPerSec
#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_SecPerTrack  pm_bpb.bpbSecPerTrack
#define pm_Heads        pm_bpb.bpbHeads
#define pm_HiddenSects  pm_bpb.bpbHiddenSecs
#define pm_HugeSectors  pm_bpb.bpbHugeSectors

/*
* Convert pointer to buffer -> pointer to direntry
*/
#define bptoep(pmp, bp, dirofs) \
       ((struct direntry *)(((char *)(bp)->b_data)     \
        + ((dirofs) & (pmp)->pm_crbomask)))

/*
* Convert sector number to cluster number
*/
#define de_bn2cn(pmp, bn) \
       ((bn) >> ((pmp)->pm_cnshift - (pmp)->pm_bnshift))

/*
* Convert cluster number to sector number
*/
#define de_cn2bn(pmp, cn) \
       ((cn) << ((pmp)->pm_cnshift - (pmp)->pm_bnshift))

/*
* Convert sector number to kernel block number
*/
#define de_bn2kb(pmp, bn) \
       ((bn) << ((pmp)->pm_bnshift - DEV_BSHIFT))

/*
* Convert kernel block number to sector number
*/
#define de_kb2bn(pmp, kb) \
       ((kb) >> ((pmp)->pm_bnshift - DEV_BSHIFT))

/*
* Convert file offset to cluster number
*/
#define de_cluster(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)

/*
* Convert file offset to sector number
*/
#define de_blk(pmp, off) \
       (de_cn2bn(pmp, de_cluster((pmp), (off))))

/*
* Convert cluster number to file offset
*/
#define de_cn2off(pmp, cn) \
       ((cn) << (pmp)->pm_cnshift)

/*
* Convert sector number to file offset
*/
#define de_bn2off(pmp, bn) \
       ((bn) << (pmp)->pm_bnshift)
/*
* Map a cluster number into a filesystem relative sector number.
*/
#define cntobn(pmp, cn) \
       (de_cn2bn((pmp), (cn)-CLUST_FIRST) + (pmp)->pm_firstcluster)

/*
* Calculate sector number for directory entry in root dir, offset dirofs
*/
#define roottobn(pmp, dirofs) \
       (de_blk((pmp), (dirofs)) + (pmp)->pm_rootdirblk)

/*
* Calculate sector number for directory entry at cluster dirclu, offset
* dirofs
*/
#define detobn(pmp, dirclu, dirofs) \
       ((dirclu) == MSDOSFSROOT \
        ? roottobn((pmp), (dirofs)) \
        : cntobn((pmp), (dirclu)))

/*
* Prototypes for MSDOSFS virtual filesystem operations
*/
void msdosfs_init(void);
void msdosfs_reinit(void);
void msdosfs_done(void);

#ifndef MAKEFS
VFS_PROTOS(msdosfs);
#endif

#endif /* _KERNEL || MAKEFS */
#endif /* _MSDOSFS_MSDOSFSMOUNT_H_ */