msdosfsmount.h revision 12144 
1/*	$Id: msdosfsmount.h,v 1.3 1995/05/30 08:07:47 rgrimes 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/*
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_mounter;	/* uid of the user who mounted the FS */
58	uid_t pm_uid;		/* uid to set as owner of the files */
59	gid_t pm_gid;		/* gid to set as owner of the files */
60	mode_t pm_mask;		/* mask to and with file protection bits */
61	struct vnode *pm_devvp;	/* vnode for block device mntd */
62	struct bpb50 pm_bpb;	/* BIOS parameter blk for this fs */
63	u_long pm_fatblk;	/* block # of first FAT */
64	u_long pm_rootdirblk;	/* block # of root directory */
65	u_long pm_rootdirsize;	/* size in blocks (not clusters) */
66	u_long pm_firstcluster;	/* block number of first cluster */
67	u_long pm_nmbrofclusters;	/* # of clusters in filesystem */
68	u_long pm_maxcluster;	/* maximum cluster number */
69	u_long pm_freeclustercount;	/* number of free clusters */
70	u_long pm_bnshift;	/* shift file offset right this amount to get a block number */
71	u_long pm_brbomask;	/* and a file offset with this mask to get block rel offset */
72	u_long pm_cnshift;	/* shift file offset right this amount to get a cluster number */
73	u_long pm_crbomask;	/* and a file offset with this mask to get cluster rel offset */
74	u_long pm_bpcluster;	/* bytes per cluster */
75	u_long pm_depclust;	/* directory entries per cluster */
76	u_long pm_fmod;		/* ~0 if fs is modified, this can rollover to 0	*/
77	u_long pm_fatblocksize;	/* size of fat blocks in bytes */
78	u_long pm_fatblocksec;	/* size of fat blocks in sectors */
79	u_long pm_fatsize;	/* size of fat in bytes */
80	u_int *pm_inusemap;	/* ptr to bitmap of in-use clusters */
81	char pm_ronly;		/* read only if non-zero */
82	char pm_waitonfat;	/* wait for writes of the fat to complt, when 0 use bdwrite, else use bwrite */
83	struct netexport pm_export;	/* export information */
84};
85
86/* Number of bits in one pm_inusemap item: */
87#define	N_INUSEBITS	(8 * sizeof(u_int))
88
89/*
90 * How to compute pm_cnshift and pm_crbomask.
91 *
92 * pm_crbomask = (pm_SectPerClust * pm_BytesPerSect) - 1
93 * if (bytesperclust == * 0)
94 * 	return EBADBLKSZ;
95 * bit = 1;
96 * for (i = 0; i < 32; i++) {
97 *	if (bit & bytesperclust) {
98 *		if (bit ^ bytesperclust)
99 *			return EBADBLKSZ;
100 *		pm_cnshift = * i;
101 *		break;
102 *	}
103 *	bit <<= 1;
104 * }
105 */
106
107/*
108 * Shorthand for fields in the bpb contained in the msdosfsmount structure.
109 */
110#define	pm_BytesPerSec	pm_bpb.bpbBytesPerSec
111#define	pm_SectPerClust	pm_bpb.bpbSecPerClust
112#define	pm_ResSectors	pm_bpb.bpbResSectors
113#define	pm_FATs		pm_bpb.bpbFATs
114#define	pm_RootDirEnts	pm_bpb.bpbRootDirEnts
115#define	pm_Sectors	pm_bpb.bpbSectors
116#define	pm_Media	pm_bpb.bpbMedia
117#define	pm_FATsecs	pm_bpb.bpbFATsecs
118#define	pm_SecPerTrack	pm_bpb.bpbSecPerTrack
119#define	pm_Heads	pm_bpb.bpbHeads
120#define	pm_HiddenSects	pm_bpb.bpbHiddenSecs
121#define	pm_HugeSectors	pm_bpb.bpbHugeSectors
122
123/*
124 * Map a cluster number into a filesystem relative block number.
125 */
126#define	cntobn(pmp, cn) \
127	((((cn)-CLUST_FIRST) * (pmp)->pm_SectPerClust) + (pmp)->pm_firstcluster)
128
129/*
130 * Map a filesystem relative block number back into a cluster number.
131 */
132#define	bntocn(pmp, bn) \
133	((((bn) - pmp->pm_firstcluster)/ (pmp)->pm_SectPerClust) + CLUST_FIRST)
134
135/*
136 * Calculate block number for directory entry in root dir, offset dirofs
137 */
138#define	roottobn(pmp, dirofs) \
139	(((dirofs) / (pmp)->pm_depclust) * (pmp)->pm_SectPerClust \
140	+ (pmp)->pm_rootdirblk)
141
142/*
143 * Calculate block number for directory entry at cluster dirclu, offset
144 * dirofs
145 */
146#define	detobn(pmp, dirclu, dirofs) \
147	((dirclu) == MSDOSFSROOT \
148	 ? roottobn((pmp), (dirofs)) \
149	 : cntobn((pmp), (dirclu)))
150
151/*
152 * Convert pointer to buffer -> pointer to direntry
153 */
154#define	bptoep(pmp, bp, dirofs) \
155	((struct direntry *)((bp)->b_data)	\
156	 + (dirofs) % (pmp)->pm_depclust)
157
158
159/*
160 * Convert filesize to block number
161 */
162#define de_blk(pmp, off) \
163	((off) >> (pmp)->pm_cnshift)
164
165/*
166 * Clusters required to hold size bytes
167 */
168#define	de_clcount(pmp, size) \
169	(((size) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift)
170
171/*
172 * Prototypes for MSDOSFS virtual filesystem operations
173 */
174static int msdosfs_mount __P((struct mount *, char *, caddr_t, struct nameidata *, struct proc *));
175static int msdosfs_start __P((struct mount *, int, struct proc *));
176static int msdosfs_unmount __P((struct mount *, int, struct proc *));
177static int msdosfs_root __P((struct mount *, struct vnode **));
178static int msdosfs_quotactl __P((struct mount *, int, uid_t, caddr_t, struct proc *));
179static int msdosfs_statfs __P((struct mount *, struct statfs *, struct proc *));
180static int msdosfs_sync __P((struct mount *, int, struct ucred *, struct proc *));
181static int msdosfs_fhtovp __P((struct mount *, struct fid *, struct mbuf *, struct vnode **, int *, struct ucred **));
182static int msdosfs_vptofh __P((struct vnode *, struct fid *));
183int msdosfs_init __P(());
184
185static int mountmsdosfs __P((struct vnode *devvp, struct mount *mp, struct proc *p));
186