xref: /netbsd-src/sys/fs/msdosfs/msdosfsmount.h (revision 500db002748d9818288e46e10f026a2b09548086)
1 /*	$NetBSD: msdosfsmount.h,v 1.15 2008/06/28 01:34:05 rumble 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 /*
54  *  Arguments to mount MSDOS filesystems.
55  */
56 struct msdosfs_args {
57 	char	*fspec;		/* blocks special holding the fs to mount */
58 	struct	export_args30 _pad1; /* compat with old userland tools */
59 	uid_t	uid;		/* uid that owns msdosfs files */
60 	gid_t	gid;		/* gid that owns msdosfs files */
61 	mode_t  mask;		/* mask to be applied for msdosfs perms */
62 	int	flags;		/* see below */
63 
64 	/* Following items added after versioning support */
65 	int	version;	/* version of the struct */
66 #define MSDOSFSMNT_VERSION	3
67 	mode_t  dirmask;	/* v2: mask to be applied for msdosfs perms */
68 	int	gmtoff;		/* v3: offset from UTC in seconds */
69 };
70 
71 /*
72  * Msdosfs mount options:
73  */
74 #define	MSDOSFSMNT_SHORTNAME	1	/* Force old DOS short names only */
75 #define	MSDOSFSMNT_LONGNAME	2	/* Force Win'95 long names */
76 #define	MSDOSFSMNT_NOWIN95	4	/* Completely ignore Win95 entries */
77 #define	MSDOSFSMNT_GEMDOSFS	8	/* This is a gemdos-flavour */
78 #define MSDOSFSMNT_VERSIONED	16	/* Struct is versioned */
79 
80 /* All flags above: */
81 #define	MSDOSFSMNT_MNTOPT \
82 	(MSDOSFSMNT_SHORTNAME|MSDOSFSMNT_LONGNAME|MSDOSFSMNT_NOWIN95 \
83 	 |MSDOSFSMNT_GEMDOSFS|MSDOSFSMNT_VERSIONED)
84 
85 #define	MSDOSFSMNT_RONLY	0x80000000	/* mounted read-only	*/
86 #define	MSDOSFSMNT_WAITONFAT	0x40000000	/* mounted synchronous	*/
87 #define	MSDOSFS_FATMIRROR	0x20000000	/* FAT is mirrored */
88 
89 #define MSDOSFSMNT_BITS "\177\20" \
90     "b\00shortname\0b\01longname\0b\02nowin95\0b\03gemdosfs\0b\04mntversioned\0" \
91     "b\037ronly\0b\036waitonfat\0b\035fatmirror\0"
92 
93 #ifdef _KERNEL
94 #include <sys/mallocvar.h>
95 MALLOC_DECLARE(M_MSDOSFSMNT);
96 MALLOC_DECLARE(M_MSDOSFSTMP);
97 
98 /*
99  * Layout of the mount control block for a msdos file system.
100  */
101 struct msdosfsmount {
102 	struct mount *pm_mountp;/* vfs mount struct for this fs */
103 	dev_t pm_dev;		/* block special device mounted */
104 	uid_t pm_uid;		/* uid to set as owner of the files */
105 	gid_t pm_gid;		/* gid to set as owner of the files */
106 	mode_t pm_mask;		/* mask to and with file protection bits
107 				   for files */
108 	mode_t pm_dirmask;	/* mask to and with file protection bits
109 				   for directories */
110 	int pm_gmtoff;		/* offset from UTC in seconds */
111 	struct vnode *pm_devvp;	/* vnode for block device mntd */
112 	struct bpb50 pm_bpb;	/* BIOS parameter blk for this fs */
113 	u_long pm_FATsecs;	/* actual number of fat sectors */
114 	u_long pm_fatblk;	/* sector # of first FAT */
115 	u_long pm_rootdirblk;	/* sector # (cluster # for FAT32) of root directory number */
116 	u_long pm_rootdirsize;	/* size in sectors (not clusters) */
117 	u_long pm_firstcluster;	/* sector number of first cluster */
118 	u_long pm_nmbrofclusters;	/* # of clusters in filesystem */
119 	u_long pm_maxcluster;	/* maximum cluster number */
120 	u_long pm_freeclustercount;	/* number of free clusters */
121 	u_long pm_cnshift;	/* shift file offset right this amount to get a cluster number */
122 	u_long pm_crbomask;	/* and a file offset with this mask to get cluster rel offset */
123 	u_long pm_bnshift;	/* shift file offset right this amount to get a sector number */
124 	u_long pm_bpcluster;	/* bytes per cluster */
125 	u_long pm_fmod;		/* ~0 if fs is modified, this can rollover to 0	*/
126 	u_long pm_fatblocksize;	/* size of fat blocks in bytes */
127 	u_long pm_fatblocksec;	/* size of fat blocks in sectors */
128 	u_long pm_fatsize;	/* size of fat in bytes */
129 	u_long pm_fatmask;	/* mask to use for fat numbers */
130 	u_long pm_fsinfo;	/* fsinfo block number */
131 	u_long pm_nxtfree;	/* next free cluster in fsinfo block */
132 	u_int pm_fatmult;	/* these 2 values are used in fat */
133 	u_int pm_fatdiv;	/*	offset computation */
134 	u_int pm_curfat;	/* current fat for FAT32 (0 otherwise) */
135 	u_int *pm_inusemap;	/* ptr to bitmap of in-use clusters */
136 	u_int pm_flags;		/* see below */
137 };
138 /* Byte offset in FAT on filesystem pmp, cluster cn */
139 #define	FATOFS(pmp, cn)	((cn) * (pmp)->pm_fatmult / (pmp)->pm_fatdiv)
140 
141 #define	VFSTOMSDOSFS(mp)	((struct msdosfsmount *)mp->mnt_data)
142 
143 /* Number of bits in one pm_inusemap item: */
144 #define	N_INUSEBITS	(8 * sizeof(u_int))
145 
146 /*
147  * Shorthand for fields in the bpb contained in the msdosfsmount structure.
148  */
149 #define	pm_BytesPerSec	pm_bpb.bpbBytesPerSec
150 #define	pm_ResSectors	pm_bpb.bpbResSectors
151 #define	pm_FATs		pm_bpb.bpbFATs
152 #define	pm_RootDirEnts	pm_bpb.bpbRootDirEnts
153 #define	pm_Sectors	pm_bpb.bpbSectors
154 #define	pm_Media	pm_bpb.bpbMedia
155 #define	pm_SecPerTrack	pm_bpb.bpbSecPerTrack
156 #define	pm_Heads	pm_bpb.bpbHeads
157 #define	pm_HiddenSects	pm_bpb.bpbHiddenSecs
158 #define	pm_HugeSectors	pm_bpb.bpbHugeSectors
159 
160 /*
161  * Convert pointer to buffer -> pointer to direntry
162  */
163 #define	bptoep(pmp, bp, dirofs) \
164 	((struct direntry *)(((char *)(bp)->b_data)	\
165 	 + ((dirofs) & (pmp)->pm_crbomask)))
166 
167 /*
168  * Convert sector number to cluster number
169  */
170 #define	de_bn2cn(pmp, bn) \
171 	((bn) >> ((pmp)->pm_cnshift - (pmp)->pm_bnshift))
172 
173 /*
174  * Convert cluster number to sector number
175  */
176 #define	de_cn2bn(pmp, cn) \
177 	((cn) << ((pmp)->pm_cnshift - (pmp)->pm_bnshift))
178 
179 /*
180  * Convert sector number to kernel block number
181  */
182 #define de_bn2kb(pmp, bn) \
183 	((bn) << ((pmp)->pm_bnshift - DEV_BSHIFT))
184 
185 /*
186  * Convert kernel block number to sector number
187  */
188 #define de_kb2bn(pmp, kb) \
189 	((kb) >> ((pmp)->pm_bnshift - DEV_BSHIFT))
190 
191 /*
192  * Convert file offset to cluster number
193  */
194 #define de_cluster(pmp, off) \
195 	((off) >> (pmp)->pm_cnshift)
196 
197 /*
198  * Clusters required to hold size bytes
199  */
200 #define	de_clcount(pmp, size) \
201 	(((size) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift)
202 
203 /*
204  * Convert file offset to sector number
205  */
206 #define de_blk(pmp, off) \
207 	(de_cn2bn(pmp, de_cluster((pmp), (off))))
208 
209 /*
210  * Convert cluster number to file offset
211  */
212 #define	de_cn2off(pmp, cn) \
213 	((cn) << (pmp)->pm_cnshift)
214 
215 /*
216  * Convert sector number to file offset
217  */
218 #define	de_bn2off(pmp, bn) \
219 	((bn) << (pmp)->pm_bnshift)
220 /*
221  * Map a cluster number into a filesystem relative sector number.
222  */
223 #define	cntobn(pmp, cn) \
224 	(de_cn2bn((pmp), (cn)-CLUST_FIRST) + (pmp)->pm_firstcluster)
225 
226 /*
227  * Calculate sector number for directory entry in root dir, offset dirofs
228  */
229 #define	roottobn(pmp, dirofs) \
230 	(de_blk((pmp), (dirofs)) + (pmp)->pm_rootdirblk)
231 
232 /*
233  * Calculate sector number for directory entry at cluster dirclu, offset
234  * dirofs
235  */
236 #define	detobn(pmp, dirclu, dirofs) \
237 	((dirclu) == MSDOSFSROOT \
238 	 ? roottobn((pmp), (dirofs)) \
239 	 : cntobn((pmp), (dirclu)))
240 
241 /*
242  * Prototypes for MSDOSFS virtual filesystem operations
243  */
244 void msdosfs_init(void);
245 void msdosfs_reinit(void);
246 void msdosfs_done(void);
247 
248 #endif /* _KERNEL */
249 #endif /* _MSDOSFS_MSDOSFSMOUNT_H_ */
250