xref: /freebsd/sys/fs/msdosfs/msdosfsmount.h (revision df7f5d4de4592a8948a25ce01e5bddfbb7ce39dc)
1 /*	$Id: msdosfsmount.h,v 1.10 1997/02/22 09:40:49 peter Exp $ */
2 /*	$NetBSD: msdosfsmount.h,v 1.7 1994/08/21 18:44:17 ws Exp $	*/
3 
4 /*-
5  * Copyright (C) 1994 Wolfgang Solfrank.
6  * Copyright (C) 1994 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 #ifndef _MSDOSFS_MSDOSFSMOUNT_H_
52 #define	_MSDOSFS_MSDOSFSMOUNT_H_
53 
54 #ifdef KERNEL
55 
56 /*
57  * Layout of the mount control block for a msdos file system.
58  */
59 struct msdosfsmount {
60 	struct mount *pm_mountp;/* vfs mount struct for this fs */
61 	dev_t pm_dev;		/* block special device mounted */
62 	uid_t pm_mounter;	/* uid of the user who mounted the FS */
63 	uid_t pm_uid;		/* uid to set as owner of the files */
64 	gid_t pm_gid;		/* gid to set as owner of the files */
65 	mode_t pm_mask;		/* mask to and with file protection bits */
66 	struct vnode *pm_devvp;	/* vnode for block device mntd */
67 	struct bpb50 pm_bpb;	/* BIOS parameter blk for this fs */
68 	u_long pm_fatblk;	/* block # of first FAT */
69 	u_long pm_rootdirblk;	/* block # of root directory */
70 	u_long pm_rootdirsize;	/* size in blocks (not clusters) */
71 	u_long pm_firstcluster;	/* block number of first cluster */
72 	u_long pm_nmbrofclusters;	/* # of clusters in filesystem */
73 	u_long pm_maxcluster;	/* maximum cluster number */
74 	u_long pm_freeclustercount;	/* number of free clusters */
75 	u_long pm_bnshift;	/* shift file offset right this amount to get a block number */
76 	u_long pm_brbomask;	/* and a file offset with this mask to get block rel offset */
77 	u_long pm_cnshift;	/* shift file offset right this amount to get a cluster number */
78 	u_long pm_crbomask;	/* and a file offset with this mask to get cluster rel offset */
79 	u_long pm_bpcluster;	/* bytes per cluster */
80 	u_long pm_depclust;	/* directory entries per cluster */
81 	u_long pm_fmod;		/* ~0 if fs is modified, this can rollover to 0	*/
82 	u_long pm_fatblocksize;	/* size of fat blocks in bytes */
83 	u_long pm_fatblocksec;	/* size of fat blocks in sectors */
84 	u_long pm_fatsize;	/* size of fat in bytes */
85 	u_int *pm_inusemap;	/* ptr to bitmap of in-use clusters */
86 	char pm_ronly;		/* read only if non-zero */
87 	char pm_waitonfat;	/* wait for writes of the fat to complete, when 0 use bdwrite, else use bwrite */
88 	struct netexport pm_export;	/* export information */
89 };
90 
91 /* Number of bits in one pm_inusemap item: */
92 #define	N_INUSEBITS	(8 * sizeof(u_int))
93 
94 /*
95  * How to compute pm_cnshift and pm_crbomask.
96  *
97  * pm_crbomask = (pm_SectPerClust * pm_BytesPerSect) - 1
98  * if (bytesperclust == * 0)
99  * 	return EBADBLKSZ;
100  * bit = 1;
101  * for (i = 0; i < 32; i++) {
102  *	if (bit & bytesperclust) {
103  *		if (bit ^ bytesperclust)
104  *			return EBADBLKSZ;
105  *		pm_cnshift = * i;
106  *		break;
107  *	}
108  *	bit <<= 1;
109  * }
110  */
111 
112 /*
113  * Shorthand for fields in the bpb contained in the msdosfsmount structure.
114  */
115 #define	pm_BytesPerSec	pm_bpb.bpbBytesPerSec
116 #define	pm_SectPerClust	pm_bpb.bpbSecPerClust
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_FATsecs	pm_bpb.bpbFATsecs
123 #define	pm_SecPerTrack	pm_bpb.bpbSecPerTrack
124 #define	pm_Heads	pm_bpb.bpbHeads
125 #define	pm_HiddenSects	pm_bpb.bpbHiddenSecs
126 #define	pm_HugeSectors	pm_bpb.bpbHugeSectors
127 
128 /*
129  * Map a cluster number into a filesystem relative block number.
130  */
131 #define	cntobn(pmp, cn) \
132 	((((cn)-CLUST_FIRST) * (pmp)->pm_SectPerClust) + (pmp)->pm_firstcluster)
133 
134 /*
135  * Map a filesystem relative block number back into a cluster number.
136  */
137 #define	bntocn(pmp, bn) \
138 	((((bn) - pmp->pm_firstcluster)/ (pmp)->pm_SectPerClust) + CLUST_FIRST)
139 
140 /*
141  * Calculate block number for directory entry in root dir, offset dirofs
142  */
143 #define	roottobn(pmp, dirofs) \
144 	(((dirofs) / (pmp)->pm_depclust) * (pmp)->pm_SectPerClust \
145 	+ (pmp)->pm_rootdirblk)
146 
147 /*
148  * Calculate block number for directory entry at cluster dirclu, offset
149  * dirofs
150  */
151 #define	detobn(pmp, dirclu, dirofs) \
152 	((dirclu) == MSDOSFSROOT \
153 	 ? roottobn((pmp), (dirofs)) \
154 	 : cntobn((pmp), (dirclu)))
155 
156 /*
157  * Convert pointer to buffer -> pointer to direntry
158  */
159 #define	bptoep(pmp, bp, dirofs) \
160 	((struct direntry *)((bp)->b_data)	\
161 	 + (dirofs) % (pmp)->pm_depclust)
162 
163 
164 /*
165  * Convert filesize to block number
166  */
167 #define de_blk(pmp, off) \
168 	((off) >> (pmp)->pm_cnshift)
169 
170 /*
171  * Clusters required to hold size bytes
172  */
173 #define	de_clcount(pmp, size) \
174 	(((size) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift)
175 
176 int msdosfs_init __P((struct vfsconf *vfsp));
177 
178 #endif /* KERNEL */
179 
180 /*
181  *  Arguments to mount MSDOS filesystems.
182  */
183 struct msdosfs_args {
184 	char	*fspec;		/* blocks special holding the fs to mount */
185 	struct	export_args export;	/* network export information */
186 	uid_t	uid;		/* uid that owns msdosfs files */
187 	gid_t	gid;		/* gid that owns msdosfs files */
188 	mode_t	mask;		/* mask to be applied for msdosfs perms */
189 };
190 
191 #endif /* !_MSDOSFS_MSDOSFSMOUNT_H_ */
192