1 /*        $NetBSD: msdosfsmount.h,v 1.21 2016/01/30 09:59:27 mlelstv Exp $      */
2 
3 /*-
4  * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
5  * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
6  * All rights reserved.
7  * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *        This product includes software developed by TooLs GmbH.
20  * 4. The name of TooLs GmbH may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
29  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
30  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
31  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
32  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 /*
35  * Written by Paul Popelka (paulp@uts.amdahl.com)
36  *
37  * You can do anything you want with this software, just don't say you wrote
38  * it, and don't remove this notice.
39  *
40  * This software is provided "as is".
41  *
42  * The author supplies this software to be publicly redistributed on the
43  * understanding that the author is not responsible for the correct
44  * functioning of this software in any circumstances and is not liable for
45  * any damages caused by this software.
46  *
47  * October 1992
48  */
49 
50 #ifndef _MSDOSFS_MSDOSFSMOUNT_H_
51 #define _MSDOSFS_MSDOSFSMOUNT_H_
52 
53 #ifndef MAKEFS
54 /*
55  *  Arguments to mount MSDOS filesystems.
56  */
57 struct msdosfs_args {
58           char      *fspec;             /* blocks special holding the fs to mount */
59           struct    export_args30 _pad1; /* compat with old userland tools */
60           uid_t     uid;                /* uid that owns msdosfs files */
61           gid_t     gid;                /* gid that owns msdosfs files */
62           mode_t  mask;                 /* mask to be applied for msdosfs perms */
63           int       flags;              /* see below */
64 
65           /* Following items added after versioning support */
66           int       version;  /* version of the struct */
67 #define MSDOSFSMNT_VERSION    3
68           mode_t  dirmask;    /* v2: mask to be applied for msdosfs perms */
69           int       gmtoff;             /* v3: offset from UTC in seconds */
70 };
71 #endif
72 
73 /*
74  * Msdosfs mount options:
75  */
76 #define   MSDOSFSMNT_SHORTNAME          1         /* Force old DOS short names only */
77 #define   MSDOSFSMNT_LONGNAME 2         /* Force Win'95 long names */
78 #define   MSDOSFSMNT_NOWIN95  4         /* Completely ignore Win95 entries */
79 #define   MSDOSFSMNT_GEMDOSFS 8         /* This is a GEMDOS-flavour */
80 #define MSDOSFSMNT_VERSIONED  16        /* Struct is versioned */
81 #define MSDOSFSMNT_UTF8                 32        /* Use UTF8 filenames */
82 
83 /* All flags above: */
84 #define   MSDOSFSMNT_MNTOPT \
85           (MSDOSFSMNT_SHORTNAME|MSDOSFSMNT_LONGNAME|MSDOSFSMNT_NOWIN95 \
86            |MSDOSFSMNT_GEMDOSFS|MSDOSFSMNT_VERSIONED|MSDOSFSMNT_UTF8)
87 
88 #define   MSDOSFSMNT_RONLY    0x80000000          /* mounted read-only          */
89 #define   MSDOSFSMNT_WAITONFAT          0x40000000          /* mounted synchronous        */
90 #define   MSDOSFS_FATMIRROR   0x20000000          /* FAT is mirrored */
91 
92 #define MSDOSFSMNT_BITS "\177\20" \
93     "b\00shortname\0b\01longname\0b\02nowin95\0b\03gemdosfs\0b\04mntversioned\0" \
94     "b\05utf8\0b\037ronly\0b\036waitonfat\0b\035fatmirror\0"
95 
96 #ifdef _KERNEL
97 #include <sys/mallocvar.h>
98 #ifdef MALLOC_DECLARE
99 MALLOC_DECLARE(M_MSDOSFSMNT);
100 MALLOC_DECLARE(M_MSDOSFSTMP);
101 #endif
102 #endif
103 
104 #if defined(_KERNEL) || defined(MAKEFS)
105 /*
106  * Layout of the mount control block for a MSDOSFS file system.
107  */
108 struct msdosfsmount {
109           struct mount *pm_mountp;/* vfs mount struct for this fs */
110           dev_t pm_dev;                 /* block special device mounted */
111           uid_t pm_uid;                 /* uid to set as owner of the files */
112           gid_t pm_gid;                 /* gid to set as owner of the files */
113           mode_t pm_mask;               /* mask to and with file protection bits
114                                            for files */
115           mode_t pm_dirmask;  /* mask to and with file protection bits
116                                            for directories */
117           int pm_gmtoff;                /* offset from UTC in seconds */
118           struct vnode *pm_devvp;       /* vnode for block device mntd */
119           struct bpb50 pm_bpb;          /* BIOS parameter blk for this fs */
120           u_long pm_FATsecs;  /* actual number of FAT sectors */
121           u_long pm_fatblk;   /* sector # of first FAT */
122           u_long pm_rootdirblk;         /* sector # (cluster # for FAT32) of root directory number */
123           u_long pm_rootdirsize;        /* size in sectors (not clusters) */
124           u_long pm_firstcluster;       /* sector number of first cluster */
125           u_long pm_nmbrofclusters;     /* # of clusters in filesystem */
126           u_long pm_maxcluster;         /* maximum cluster number */
127           u_long pm_freeclustercount;   /* number of free clusters */
128           u_long pm_cnshift;  /* shift file offset right this amount to get a cluster number */
129           u_long pm_crbomask; /* and a file offset with this mask to get cluster rel offset */
130           u_long pm_bnshift;  /* shift file offset right this amount to get a sector number */
131           u_long pm_bpcluster;          /* bytes per cluster */
132           u_long pm_fmod;               /* ~0 if fs is modified, this can rollover to 0   */
133           u_long pm_fatblocksize;       /* size of FAT blocks in bytes */
134           u_long pm_fatblocksec;        /* size of FAT blocks in sectors */
135           u_long pm_fatsize;  /* size of FAT in bytes */
136           u_long pm_fatmask;  /* mask to use for FAT numbers */
137           u_long pm_fsinfo;   /* fsinfo block number */
138           u_long pm_nxtfree;  /* next free cluster in fsinfo block */
139           u_int pm_fatmult;   /* these 2 values are used in FAT */
140           u_int pm_fatdiv;    /*        offset computation */
141           u_int pm_curfat;    /* current FAT for FAT32 (0 otherwise) */
142           u_int *pm_inusemap; /* ptr to bitmap of in-use clusters */
143           u_int pm_flags;               /* see below */
144 };
145 /* Byte offset in FAT on filesystem pmp, cluster cn */
146 #define   FATOFS(pmp, cn)     ((cn) * (pmp)->pm_fatmult / (pmp)->pm_fatdiv)
147 
148 #define   VFSTOMSDOSFS(mp)    ((struct msdosfsmount *)mp->mnt_data)
149 
150 /* Number of bits in one pm_inusemap item: */
151 #define   N_INUSEBITS         (8 * sizeof(u_int))
152 
153 /*
154  * Shorthand for fields in the bpb contained in the msdosfsmount structure.
155  */
156 #define   pm_BytesPerSec      pm_bpb.bpbBytesPerSec
157 #define   pm_ResSectors       pm_bpb.bpbResSectors
158 #define   pm_FATs             pm_bpb.bpbFATs
159 #define   pm_RootDirEnts      pm_bpb.bpbRootDirEnts
160 #define   pm_Sectors          pm_bpb.bpbSectors
161 #define   pm_Media  pm_bpb.bpbMedia
162 #define   pm_SecPerTrack      pm_bpb.bpbSecPerTrack
163 #define   pm_Heads  pm_bpb.bpbHeads
164 #define   pm_HiddenSects      pm_bpb.bpbHiddenSecs
165 #define   pm_HugeSectors      pm_bpb.bpbHugeSectors
166 
167 /*
168  * Convert pointer to buffer -> pointer to direntry
169  */
170 #define   bptoep(pmp, bp, dirofs) \
171           ((struct direntry *)(((char *)(bp)->b_data)       \
172            + ((dirofs) & (pmp)->pm_crbomask)))
173 
174 /*
175  * Convert sector number to cluster number
176  */
177 #define   de_bn2cn(pmp, bn) \
178           ((bn) >> ((pmp)->pm_cnshift - (pmp)->pm_bnshift))
179 
180 /*
181  * Convert cluster number to sector number
182  */
183 #define   de_cn2bn(pmp, cn) \
184           ((cn) << ((pmp)->pm_cnshift - (pmp)->pm_bnshift))
185 
186 /*
187  * Convert sector number to kernel block number
188  */
189 #define de_bn2kb(pmp, bn) \
190           ((bn) << ((pmp)->pm_bnshift - DEV_BSHIFT))
191 
192 /*
193  * Convert kernel block number to sector number
194  */
195 #define de_kb2bn(pmp, kb) \
196           ((kb) >> ((pmp)->pm_bnshift - DEV_BSHIFT))
197 
198 /*
199  * Convert file offset to cluster number
200  */
201 #define de_cluster(pmp, off) \
202           ((off) >> (pmp)->pm_cnshift)
203 
204 /*
205  * Clusters required to hold size bytes
206  */
207 #define   de_clcount(pmp, size) \
208           (((size) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift)
209 
210 /*
211  * Convert file offset to sector number
212  */
213 #define de_blk(pmp, off) \
214           (de_cn2bn(pmp, de_cluster((pmp), (off))))
215 
216 /*
217  * Convert cluster number to file offset
218  */
219 #define   de_cn2off(pmp, cn) \
220           ((cn) << (pmp)->pm_cnshift)
221 
222 /*
223  * Convert sector number to file offset
224  */
225 #define   de_bn2off(pmp, bn) \
226           ((bn) << (pmp)->pm_bnshift)
227 /*
228  * Map a cluster number into a filesystem relative sector number.
229  */
230 #define   cntobn(pmp, cn) \
231           (de_cn2bn((pmp), (cn)-CLUST_FIRST) + (pmp)->pm_firstcluster)
232 
233 /*
234  * Calculate sector number for directory entry in root dir, offset dirofs
235  */
236 #define   roottobn(pmp, dirofs) \
237           (de_blk((pmp), (dirofs)) + (pmp)->pm_rootdirblk)
238 
239 /*
240  * Calculate sector number for directory entry at cluster dirclu, offset
241  * dirofs
242  */
243 #define   detobn(pmp, dirclu, dirofs) \
244           ((dirclu) == MSDOSFSROOT \
245            ? roottobn((pmp), (dirofs)) \
246            : cntobn((pmp), (dirclu)))
247 
248 /*
249  * Prototypes for MSDOSFS virtual filesystem operations
250  */
251 void msdosfs_init(void);
252 void msdosfs_reinit(void);
253 void msdosfs_done(void);
254 
255 #ifndef MAKEFS
256 VFS_PROTOS(msdosfs);
257 #endif
258 
259 #endif /* _KERNEL || MAKEFS */
260 #endif /* _MSDOSFS_MSDOSFSMOUNT_H_ */
261