xref: /netbsd-src/sys/fs/msdosfs/denode.h (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: denode.h,v 1.4 2003/09/07 22:09:11 itojun 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 #include <miscfs/genfs/genfs_node.h>
51 
52 /*
53  * This is the pc filesystem specific portion of the vnode structure.
54  *
55  * To describe a file uniquely the de_dirclust, de_diroffset, and
56  * de_StartCluster fields are used.
57  *
58  * de_dirclust contains the cluster number of the directory cluster
59  *	containing the entry for a file or directory.
60  * de_diroffset is the index into the cluster for the entry describing
61  *	a file or directory.
62  * de_StartCluster is the number of the first cluster of the file or directory.
63  *
64  * Now to describe the quirks of the pc filesystem.
65  * - Clusters 0 and 1 are reserved.
66  * - The first allocatable cluster is 2.
67  * - The root directory is of fixed size and all blocks that make it up
68  *   are contiguous.
69  * - Cluster 0 refers to the root directory when it is found in the
70  *   startcluster field of a directory entry that points to another directory.
71  * - Cluster 0 implies a 0 length file when found in the start cluster field
72  *   of a directory entry that points to a file.
73  * - You can't use the cluster number 0 to derive the address of the root
74  *   directory.
75  * - Multiple directory entries can point to a directory. The entry in the
76  *   parent directory points to a child directory.  Any directories in the
77  *   child directory contain a ".." entry that points back to the parent.
78  *   The child directory itself contains a "." entry that points to itself.
79  * - The root directory does not contain a "." or ".." entry.
80  * - Directory entries for directories are never changed once they are created
81  *   (except when removed).  The size stays 0, and the last modification time
82  *   is never changed.  This is because so many directory entries can point to
83  *   the physical clusters that make up a directory.  It would lead to an
84  *   update nightmare.
85  * - The length field in a directory entry pointing to a directory contains 0
86  *   (always).  The only way to find the end of a directory is to follow the
87  *   cluster chain until the "last cluster" marker is found.
88  *
89  * My extensions to make this house of cards work.  These apply only to the in
90  * memory copy of the directory entry.
91  * - A reference count for each denode will be kept since dos doesn't keep such
92  *   things.
93  */
94 
95 /*
96  * Internal pseudo-offset for (nonexistent) directory entry for the root
97  * dir in the root dir
98  */
99 #define	MSDOSFSROOT_OFS	0x1fffffff
100 
101 /*
102  * The fat cache structure. fc_fsrcn is the filesystem relative cluster
103  * number that corresponds to the file relative cluster number in this
104  * structure (fc_frcn).
105  */
106 struct fatcache {
107 	u_long fc_frcn;		/* file relative cluster number */
108 	u_long fc_fsrcn;	/* filesystem relative cluster number */
109 };
110 
111 /*
112  * The fat entry cache as it stands helps make extending files a "quick"
113  * operation by avoiding having to scan the fat to discover the last
114  * cluster of the file. The cache also helps sequential reads by
115  * remembering the last cluster read from the file.  This also prevents us
116  * from having to rescan the fat to find the next cluster to read.  This
117  * cache is probably pretty worthless if a file is opened by multiple
118  * processes.
119  */
120 #define	FC_SIZE		2	/* number of entries in the cache */
121 #define	FC_LASTMAP	0	/* entry the last call to pcbmap() resolved
122 				 * to */
123 #define	FC_LASTFC	1	/* entry for the last cluster in the file */
124 
125 #define	FCE_EMPTY	0xffffffff	/* doesn't represent an actual cluster # */
126 
127 /*
128  * Set a slot in the fat cache.
129  */
130 #define	fc_setcache(dep, slot, frcn, fsrcn) \
131 	(dep)->de_fc[slot].fc_frcn = frcn; \
132 	(dep)->de_fc[slot].fc_fsrcn = fsrcn;
133 
134 /*
135  * This is the in memory variant of a dos directory entry.  It is usually
136  * contained within a vnode.
137  */
138 struct denode {
139 	struct genfs_node de_gnode;
140 	LIST_ENTRY(denode) de_hash;
141 	struct vnode *de_vnode;	/* addr of vnode we are part of */
142 	struct vnode *de_devvp;	/* vnode of blk dev we live on */
143 	u_long de_flag;		/* flag bits */
144 	dev_t de_dev;		/* device where direntry lives */
145 	u_long de_dirclust;	/* cluster of the directory file containing this entry */
146 	u_long de_diroffset;	/* offset of this entry in the directory cluster */
147 	u_long de_fndoffset;	/* offset of found dir entry */
148 	int de_fndcnt;		/* number of slots before de_fndoffset */
149 	long de_refcnt;		/* reference count */
150 	struct msdosfsmount *de_pmp;	/* addr of our mount struct */
151 	struct lockf *de_lockf;	/* byte level lock list */
152 	u_char de_Name[12];	/* name, from DOS directory entry */
153 	u_char de_Attributes;	/* attributes, from directory entry */
154 	u_char de_CHun;		/* Hundredth of second of CTime*/
155 	u_short de_CTime;	/* creation time */
156 	u_short de_CDate;	/* creation date */
157 	u_short de_ADate;	/* access date */
158 	u_short de_MTime;	/* modification time */
159 	u_short de_MDate;	/* modification date */
160 	u_long de_StartCluster; /* starting cluster of file */
161 	u_long de_FileSize;	/* size of file in bytes */
162 	struct fatcache de_fc[FC_SIZE];	/* fat cache */
163 };
164 
165 /*
166  * Values for the de_flag field of the denode.
167  */
168 #define	DE_UPDATE	0x0001	/* Modification time update request. */
169 #define	DE_CREATE	0x0002	/* Creation time update */
170 #define	DE_ACCESS	0x0004	/* Access time update */
171 #define	DE_MODIFIED	0x0008	/* Denode has been modified. */
172 #define	DE_RENAME	0x0010	/* Denode is in the process of being renamed */
173 
174 /*
175  * Maximum filename length in Win95
176  * Note: Must be < sizeof(dirent.d_name)
177  */
178 #define	WIN_MAXLEN	255
179 
180 /*
181  * Transfer directory entries between internal and external form.
182  * dep is a struct denode * (internal form),
183  * dp is a struct direntry * (external form).
184  */
185 #define DE_INTERNALIZE32(dep, dp)			\
186 	 ((dep)->de_StartCluster |= getushort((dp)->deHighClust) << 16)
187 #define DE_INTERNALIZE(dep, dp)				\
188 	(memcpy((dep)->de_Name, (dp)->deName, 11),	\
189 	 (dep)->de_Attributes = (dp)->deAttributes,	\
190 	 (dep)->de_CHun = (dp)->deCHundredth,		\
191 	 (dep)->de_CTime = getushort((dp)->deCTime),	\
192 	 (dep)->de_CDate = getushort((dp)->deCDate),	\
193 	 (dep)->de_ADate = getushort((dp)->deADate),	\
194 	 (dep)->de_MTime = getushort((dp)->deMTime),	\
195 	 (dep)->de_MDate = getushort((dp)->deMDate),	\
196 	 (dep)->de_StartCluster = getushort((dp)->deStartCluster), \
197 	 (dep)->de_FileSize = getulong((dp)->deFileSize), \
198 	 (FAT32((dep)->de_pmp) ? DE_INTERNALIZE32((dep), (dp)) : 0))
199 
200 #define DE_EXTERNALIZE32(dp, dep)			\
201 	 putushort((dp)->deHighClust, (dep)->de_StartCluster >> 16)
202 #define DE_EXTERNALIZE(dp, dep)				\
203 	(memcpy((dp)->deName, (dep)->de_Name, 11),	\
204 	 (dp)->deAttributes = (dep)->de_Attributes,	\
205 	 (dp)->deCHundredth = (dep)->de_CHun,		\
206 	 putushort((dp)->deCTime, (dep)->de_CTime),	\
207 	 putushort((dp)->deCDate, (dep)->de_CDate),	\
208 	 putushort((dp)->deADate, (dep)->de_ADate),	\
209 	 putushort((dp)->deMTime, (dep)->de_MTime),	\
210 	 putushort((dp)->deMDate, (dep)->de_MDate),	\
211 	 putushort((dp)->deStartCluster, (dep)->de_StartCluster), \
212 	 putulong((dp)->deFileSize,			\
213 	     ((dep)->de_Attributes & ATTR_DIRECTORY) ? 0 : (dep)->de_FileSize), \
214 	 (FAT32((dep)->de_pmp) ? DE_EXTERNALIZE32((dp), (dep)) : 0))
215 
216 #define	de_forw		de_chain[0]
217 #define	de_back		de_chain[1]
218 
219 #ifdef _KERNEL
220 
221 #define	VTODE(vp)	((struct denode *)(vp)->v_data)
222 #define	DETOV(de)	((de)->de_vnode)
223 
224 #define	DETIMES(dep, acc, mod, cre, gmtoff) \
225 	if ((dep)->de_flag & (DE_UPDATE | DE_CREATE | DE_ACCESS)) { \
226 		(dep)->de_flag |= DE_MODIFIED; \
227 		if ((dep)->de_flag & DE_UPDATE) { \
228 			unix2dostime((mod), gmtoff, &(dep)->de_MDate, &(dep)->de_MTime, NULL); \
229 			(dep)->de_Attributes |= ATTR_ARCHIVE; \
230 		} \
231 		if (!((dep)->de_pmp->pm_flags & MSDOSFSMNT_NOWIN95)) { \
232 			if ((dep)->de_flag & DE_ACCESS) \
233 				unix2dostime((acc), gmtoff, &(dep)->de_ADate, NULL, NULL); \
234 			if ((dep)->de_flag & DE_CREATE) \
235 				unix2dostime((cre), gmtoff, &(dep)->de_CDate, &(dep)->de_CTime, &(dep)->de_CHun); \
236 		} \
237 		(dep)->de_flag &= ~(DE_UPDATE | DE_CREATE | DE_ACCESS); \
238 	}
239 
240 /*
241  * This overlays the fid structure (see mount.h)
242  */
243 struct defid {
244 	u_int16_t defid_len;	/* length of structure */
245 	u_int16_t defid_pad;	/* force 4-byte alignment */
246 
247 	u_int32_t defid_dirclust; /* cluster this dir entry came from */
248 	u_int32_t defid_dirofs;	/* offset of entry within the cluster */
249 #if 0
250 	u_int32_t defid_gen;	/* generation number */
251 #endif
252 };
253 
254 /*
255  * Prototypes for MSDOSFS vnode operations
256  */
257 int	msdosfs_lookup		__P((void *));
258 int	msdosfs_create		__P((void *));
259 int	msdosfs_mknod		__P((void *));
260 int	msdosfs_open		__P((void *));
261 int	msdosfs_close		__P((void *));
262 int	msdosfs_access		__P((void *));
263 int	msdosfs_getattr		__P((void *));
264 int	msdosfs_setattr		__P((void *));
265 int	msdosfs_read		__P((void *));
266 int	msdosfs_write		__P((void *));
267 #define	msdosfs_lease_check	genfs_lease_check
268 #define	msdosfs_ioctl		genfs_enoioctl
269 #define	msdosfs_poll		genfs_poll
270 #define	msdosfs_revoke		genfs_revoke
271 #define	msdosfs_mmap		genfs_mmap
272 #define	msdosfs_fsync		genfs_fsync
273 #define	msdosfs_seek		genfs_seek
274 int	msdosfs_remove		__P((void *));
275 int	msdosfs_link		__P((void *));
276 int	msdosfs_rename		__P((void *));
277 int	msdosfs_mkdir		__P((void *));
278 int	msdosfs_rmdir		__P((void *));
279 int	msdosfs_symlink		__P((void *));
280 int	msdosfs_readdir		__P((void *));
281 int	msdosfs_readlink	__P((void *));
282 #define	msdosfs_abortop		genfs_abortop
283 int	msdosfs_inactive	__P((void *));
284 int	msdosfs_reclaim		__P((void *));
285 int	msdosfs_bmap		__P((void *));
286 int	msdosfs_strategy	__P((void *));
287 int	msdosfs_print		__P((void *));
288 int	msdosfs_advlock		__P((void *));
289 int	msdosfs_reallocblks	__P((void *));
290 int	msdosfs_pathconf	__P((void *));
291 int	msdosfs_update		__P((void *));
292 
293 /*
294  * Internal service routine prototypes.
295  */
296 int createde __P((struct denode *, struct denode *, struct denode **, struct componentname *));
297 int deextend __P((struct denode *, u_long, struct ucred *));
298 int deget __P((struct msdosfsmount *, u_long, u_long, struct denode **));
299 int detrunc __P((struct denode *, u_long, int, struct ucred *, struct proc *));
300 int deupdat __P((struct denode *, int));
301 int doscheckpath __P((struct denode *, struct denode *));
302 int dosdirempty __P((struct denode *));
303 int readde __P((struct denode *, struct buf **, struct direntry **));
304 int readep __P((struct msdosfsmount *, u_long, u_long, struct buf **, struct direntry **));
305 void reinsert __P((struct denode *));
306 int removede __P((struct denode *, struct denode *));
307 int uniqdosname __P((struct denode *, struct componentname *, u_char *));
308 int findwin95 __P((struct denode *));
309 int msdosfs_gop_alloc __P((struct vnode *, off_t, off_t, int, struct ucred *));
310 #endif	/* _KERNEL */
311