1/* $OpenBSD: msdosfsmount.h,v 1.23 2024/05/13 01:15:53 jsg Exp $ */
2/* $NetBSD: msdosfsmount.h,v 1.16 1997/10/17 11:24:24 ws Exp $ */
3
4/*-
5 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
6 * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
7 * All rights reserved.
8 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by TooLs GmbH.
21 * 4. The name of TooLs GmbH may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
29 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
30 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
32 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
33 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35/*
36 * Written by Paul Popelka (paulp@uts.amdahl.com)
37 *
38 * You can do anything you want with this software, just don't say you wrote
39 * it, and don't remove this notice.
40 *
41 * This software is provided "as is".
42 *
43 * The author supplies this software to be publicly redistributed on the
44 * understanding that the author is not responsible for the correct
45 * functioning of this software in any circumstances and is not liable for
46 * any damages caused by this software.
47 *
48 * October 1992
49 */
50
51/*
52 * Layout of the mount control block for a msdos file system.
53 */
54struct msdosfsmount {
55 struct mount *pm_mountp;/* vfs mount struct for this fs */
56 dev_t pm_dev; /* block special device mounted */
57 uid_t pm_uid; /* uid to set as owner of the files */
58 gid_t pm_gid; /* gid to set as owner of the files */
59 mode_t pm_mask; /* mask to and with file protection bits */
60 struct vnode *pm_devvp; /* vnode for block device mntd */
61 struct bpb50 pm_bpb; /* BIOS parameter blk for this fs */
62 uint32_t pm_BlkPerSec; /* # of DEV_BSIZE blocks in MSDOSFS sector */
63 uint32_t pm_FATsecs; /* actual number of fat sectors */
64 uint32_t pm_fatblk; /* block # of first FAT */
65 uint32_t pm_rootdirblk; /* block # (cluster # for FAT32) of root directory number */
66 uint32_t pm_rootdirsize; /* size in blocks (not clusters) */
67 uint32_t pm_firstcluster; /* block number of first cluster */
68 uint32_t pm_nmbrofclusters; /* # of clusters in filesystem */
69 uint32_t pm_maxcluster; /* maximum cluster number */
70 uint32_t pm_freeclustercount; /* number of free clusters */
71 uint32_t pm_cnshift; /* shift file offset right this amount to get a cluster number */
72 uint32_t pm_crbomask; /* and a file offset with this mask to get cluster rel offset */
73 uint32_t pm_bnshift; /* shift file offset right this amount to get a block number */
74 uint32_t pm_bpcluster; /* bytes per cluster */
75 uint32_t pm_fmod; /* ~0 if fs is modified, this can rollover to 0 */
76 uint32_t pm_fatblocksize; /* size of fat blocks in bytes */
77 uint32_t pm_fatblocksec; /* size of fat blocks in sectors */
78 uint32_t pm_fatsize; /* size of fat in bytes */
79 uint32_t pm_fatmask; /* mask to use for fat numbers */
80 uint32_t pm_fsinfo; /* fsinfo block number */
81 u_int pm_fatmult; /* these 2 values are used in fat */
82 u_int pm_fatdiv; /* offset computation */
83 u_int pm_curfat; /* current fat for FAT32 (0 otherwise) */
84 u_int *pm_inusemap; /* ptr to bitmap of in-use clusters */
85 u_int pm_flags; /* see below */
86 struct netexport pm_export; /* export information */
87};
88/* Byte offset in FAT on filesystem pmp, cluster cn */
89#define FATOFS(pmp, cn) ((cn) * (pmp)->pm_fatmult / (pmp)->pm_fatdiv)
90
91/*
92 * Mount point flags:
93 */
94#if 0
95 /* Defined in <sys/mount.h> */
96#define MSDOSFSMNT_SHORTNAME 0x01
97#define MSDOSFSMNT_LONGNAME 0x02
98#define MSDOSFSMNT_NOWIN95 0x04
99#endif
100
101/* All flags above: */
102#define MSDOSFSMNT_MNTOPT \
103 (MSDOSFSMNT_SHORTNAME|MSDOSFSMNT_LONGNAME|MSDOSFSMNT_NOWIN95)
104#define MSDOSFSMNT_RONLY 0x80000000 /* mounted read-only */
105#define MSDOSFSMNT_WAITONFAT 0x40000000 /* mounted synchronous */
106#define MSDOSFS_FATMIRROR 0x20000000 /* FAT is mirrored */
107
108#define VFSTOMSDOSFS(mp) ((struct msdosfsmount *)mp->mnt_data)
109
110/* Number of bits in one pm_inusemap item: */
111#define N_INUSEBITS (8 * sizeof(u_int))
112
113/*
114 * Shorthand for fields in the bpb contained in the msdosfsmount structure.
115 */
116#define pm_BytesPerSec pm_bpb.bpbBytesPerSec
117#define pm_ResSectors pm_bpb.bpbResSectors
118#define pm_FATs pm_bpb.bpbFATs
119#define pm_RootDirEnts pm_bpb.bpbRootDirEnts
120#define pm_Sectors pm_bpb.bpbSectors
121#define pm_Media pm_bpb.bpbMedia
122#define pm_SecPerTrack pm_bpb.bpbSecPerTrack
123#define pm_Heads pm_bpb.bpbHeads
124#define pm_HiddenSects pm_bpb.bpbHiddenSecs
125#define pm_HugeSectors pm_bpb.bpbHugeSectors
126
127/*
128 * Convert pointer to buffer -> pointer to direntry
129 */
130#define bptoep(pmp, bp, dirofs) \
131 ((struct direntry *)(((bp)->b_data) \
132 + ((dirofs) & (pmp)->pm_crbomask)))
133
134/*
135 * Convert block number to cluster number
136 */
137#define de_bn2cn(pmp, bn) \
138 ((bn) >> ((pmp)->pm_cnshift - (pmp)->pm_bnshift))
139
140/*
141 * Convert cluster number to block number
142 */
143#define de_cn2bn(pmp, cn) \
144 ((cn) << ((pmp)->pm_cnshift - (pmp)->pm_bnshift))
145
146/*
147 * Convert file offset to cluster number
148 */
149#define de_cluster(pmp, off) \
150 ((off) >> (pmp)->pm_cnshift)
151
152/*
153 * Clusters required to hold size bytes
154 */
155#define de_clcount(pmp, size) \
156 (((size) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift)
157
158/*
159 * Convert file offset to block number
160 */
161#define de_blk(pmp, off) \
162 (de_cn2bn(pmp, de_cluster((pmp), (off))))
163
164/*
165 * Convert cluster number to file offset
166 */
167#define de_cn2off(pmp, cn) \
168 ((cn) << (pmp)->pm_cnshift)
169
170/*
171 * Convert block number to file offset
172 */
173#define de_bn2off(pmp, bn) \
174 ((bn) << (pmp)->pm_bnshift)
175/*
176 * Map a cluster number into a filesystem relative block number.
177 */
178#define cntobn(pmp, cn) \
179 (de_cn2bn((pmp), (cn)-CLUST_FIRST) + (pmp)->pm_firstcluster)
180
181/*
182 * Calculate block number for directory entry in root dir, offset dirofs
183 */
184#define roottobn(pmp, dirofs) \
185 (de_blk((pmp), (dirofs)) + (pmp)->pm_rootdirblk)
186
187/*
188 * Calculate block number for directory entry at cluster dirclu, offset
189 * dirofs
190 */
191#define detobn(pmp, dirclu, dirofs) \
192 ((dirclu) == MSDOSFSROOT \
193 ? roottobn((pmp), (dirofs)) \
194 : cntobn((pmp), (dirclu)))
195
196/* Calculate size of fsinfo block */
197#define fsi_size(pmp) \
198 (1024 << ((pmp)->pm_BlkPerSec >> 2))
199
200/*
201 * Prototypes for MSDOSFS virtual filesystem operations
202 */
203int msdosfs_mount(struct mount *, const char *, void *, struct nameidata *, struct proc *);
204int msdosfs_start(struct mount *, int, struct proc *);
205int msdosfs_unmount(struct mount *, int, struct proc *);
206int msdosfs_root(struct mount *, struct vnode **);
207int msdosfs_statfs(struct mount *, struct statfs *, struct proc *);
208int msdosfs_sync(struct mount *, int, int, struct ucred *, struct proc *);
209int msdosfs_fhtovp(struct mount *, struct fid *, struct vnode **);
210int msdosfs_vptofh(struct vnode *, struct fid *);
211int msdosfs_init(struct vfsconf *);