xref: /dragonfly/sys/vfs/msdosfs/denode.h (revision 9dbf638f)
1 /* $FreeBSD: src/sys/msdosfs/denode.h,v 1.20 1999/12/29 04:54:52 peter Exp $ */
2 /* $DragonFly: src/sys/vfs/msdosfs/denode.h,v 1.5 2003/08/20 09:56:32 rob Exp $ */
3 /*	$NetBSD: denode.h,v 1.25 1997/11/17 15:36:28 ws Exp $	*/
4 
5 /*-
6  * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
7  * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
8  * All rights reserved.
9  * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by TooLs GmbH.
22  * 4. The name of TooLs GmbH may not be used to endorse or promote products
23  *    derived from this software without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
26  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
29  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
30  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
31  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
32  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
33  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
34  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35  */
36 /*
37  * Written by Paul Popelka (paulp@uts.amdahl.com)
38  *
39  * You can do anything you want with this software, just don't say you wrote
40  * it, and don't remove this notice.
41  *
42  * This software is provided "as is".
43  *
44  * The author supplies this software to be publicly redistributed on the
45  * understanding that the author is not responsible for the correct
46  * functioning of this software in any circumstances and is not liable for
47  * any damages caused by this software.
48  *
49  * October 1992
50  */
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 lock de_lock;	/* denode lock >Keep this first< */
140 	struct denode *de_next;	/* Hash chain forward */
141 	struct denode **de_prev; /* Hash chain back */
142 	struct vnode *de_vnode;	/* addr of vnode we are part of */
143 	struct vnode *de_devvp;	/* vnode of blk dev we live on */
144 	u_long de_flag;		/* flag bits */
145 	dev_t de_dev;		/* device where direntry lives */
146 	u_long de_dirclust;	/* cluster of the directory file containing this entry */
147 	u_long de_diroffset;	/* offset of this entry in the directory cluster */
148 	u_long de_fndoffset;	/* offset of found dir entry */
149 	int de_fndcnt;		/* number of slots before de_fndoffset */
150 	long de_refcnt;		/* reference count */
151 	struct msdosfsmount *de_pmp;	/* addr of our mount struct */
152 	u_char de_Name[12];	/* name, from DOS directory entry */
153 	u_char de_Attributes;	/* attributes, from directory entry */
154 	u_char de_LowerCase;	/* NT VFAT lower case flags */
155 	u_char de_CHun;		/* Hundredth of second of CTime*/
156 	u_short de_CTime;	/* creation time */
157 	u_short de_CDate;	/* creation date */
158 	u_short de_ADate;	/* access date */
159 	u_short de_MTime;	/* modification time */
160 	u_short de_MDate;	/* modification date */
161 	u_long de_StartCluster; /* starting cluster of file */
162 	u_long de_FileSize;	/* size of file in bytes */
163 	struct fatcache de_fc[FC_SIZE];	/* fat cache */
164 	u_quad_t de_modrev;	/* Revision level for lease. */
165 };
166 
167 /*
168  * Values for the de_flag field of the denode.
169  */
170 #define	DE_UPDATE	0x0004	/* Modification time update request */
171 #define	DE_CREATE	0x0008	/* Creation time update */
172 #define	DE_ACCESS	0x0010	/* Access time update */
173 #define	DE_MODIFIED	0x0020	/* Denode has been modified */
174 #define	DE_RENAME	0x0040	/* Denode is in the process of being renamed */
175 
176 
177 /*
178  * Transfer directory entries between internal and external form.
179  * dep is a struct denode * (internal form),
180  * dp is a struct direntry * (external form).
181  */
182 #define DE_INTERNALIZE32(dep, dp)			\
183 	 ((dep)->de_StartCluster |= getushort((dp)->deHighClust) << 16)
184 #define DE_INTERNALIZE(dep, dp)				\
185 	(bcopy((dp)->deName, (dep)->de_Name, 11),	\
186 	 (dep)->de_Attributes = (dp)->deAttributes,	\
187 	 (dep)->de_LowerCase = (dp)->deLowerCase,	\
188 	 (dep)->de_CHun = (dp)->deCHundredth,		\
189 	 (dep)->de_CTime = getushort((dp)->deCTime),	\
190 	 (dep)->de_CDate = getushort((dp)->deCDate),	\
191 	 (dep)->de_ADate = getushort((dp)->deADate),	\
192 	 (dep)->de_MTime = getushort((dp)->deMTime),	\
193 	 (dep)->de_MDate = getushort((dp)->deMDate),	\
194 	 (dep)->de_StartCluster = getushort((dp)->deStartCluster), \
195 	 (dep)->de_FileSize = getulong((dp)->deFileSize), \
196 	 (FAT32((dep)->de_pmp) ? DE_INTERNALIZE32((dep), (dp)) : 0))
197 
198 #define DE_EXTERNALIZE(dp, dep)				\
199 	(bcopy((dep)->de_Name, (dp)->deName, 11),	\
200 	 (dp)->deAttributes = (dep)->de_Attributes,	\
201 	 (dp)->deLowerCase = (dep)->de_LowerCase,	\
202 	 (dp)->deCHundredth = (dep)->de_CHun,		\
203 	 putushort((dp)->deCTime, (dep)->de_CTime),	\
204 	 putushort((dp)->deCDate, (dep)->de_CDate),	\
205 	 putushort((dp)->deADate, (dep)->de_ADate),	\
206 	 putushort((dp)->deMTime, (dep)->de_MTime),	\
207 	 putushort((dp)->deMDate, (dep)->de_MDate),	\
208 	 putushort((dp)->deStartCluster, (dep)->de_StartCluster), \
209 	 putulong((dp)->deFileSize,			\
210 	     ((dep)->de_Attributes & ATTR_DIRECTORY) ? 0 : (dep)->de_FileSize), \
211 	 putushort((dp)->deHighClust, (dep)->de_StartCluster >> 16))
212 
213 #define	de_forw		de_chain[0]
214 #define	de_back		de_chain[1]
215 
216 #ifdef _KERNEL
217 
218 #define	VTODE(vp)	((struct denode *)(vp)->v_data)
219 #define	DETOV(de)	((de)->de_vnode)
220 
221 #define	DETIMES(dep, acc, mod, cre) do {				\
222 	if ((dep)->de_flag & DE_UPDATE) { 				\
223 		(dep)->de_flag |= DE_MODIFIED;				\
224 		unix2dostime((mod), &(dep)->de_MDate, &(dep)->de_MTime,	\
225 		    NULL);						\
226 		(dep)->de_Attributes |= ATTR_ARCHIVE; 			\
227 	}								\
228 	if ((dep)->de_pmp->pm_flags & MSDOSFSMNT_NOWIN95) {		\
229 		(dep)->de_flag &= ~(DE_UPDATE | DE_CREATE | DE_ACCESS);	\
230 		break;							\
231 	}								\
232 	if ((dep)->de_flag & DE_ACCESS) {				\
233 	    	u_int16_t adate;					\
234 									\
235 		unix2dostime((acc), &adate, NULL, NULL);		\
236 		if (adate != (dep)->de_ADate) {				\
237 			(dep)->de_flag |= DE_MODIFIED;			\
238 			(dep)->de_ADate = adate;			\
239 		}							\
240 	}								\
241 	if ((dep)->de_flag & DE_CREATE) {				\
242 		unix2dostime((cre), &(dep)->de_CDate, &(dep)->de_CTime,	\
243 		    &(dep)->de_CHun);					\
244 		    (dep)->de_flag |= DE_MODIFIED;			\
245 	}								\
246 	(dep)->de_flag &= ~(DE_UPDATE | DE_CREATE | DE_ACCESS);		\
247 } while (0);
248 
249 /*
250  * This overlays the fid structure (see mount.h)
251  */
252 struct defid {
253 	u_short defid_len;	/* length of structure */
254 	u_short defid_pad;	/* force long alignment */
255 
256 	u_long defid_dirclust;	/* cluster this dir entry came from */
257 	u_long defid_dirofs;	/* offset of entry within the cluster */
258 #if 0
259 	u_long	defid_gen;	/* generation number */
260 #endif
261 };
262 
263 extern vop_t **msdosfs_vnodeop_p;
264 
265 int msdosfs_lookup (struct vop_cachedlookup_args *);
266 int msdosfs_inactive (struct vop_inactive_args *);
267 int msdosfs_reclaim (struct vop_reclaim_args *);
268 
269 /*
270  * Internal service routine prototypes.
271  */
272 int deget (struct msdosfsmount *, u_long, u_long, struct denode **);
273 int uniqdosname (struct denode *, struct componentname *, u_char *);
274 int findwin95 (struct denode *);
275 
276 int readep (struct msdosfsmount *pmp, u_long dirclu, u_long dirofs,  struct buf **bpp, struct direntry **epp);
277 int readde (struct denode *dep, struct buf **bpp, struct direntry **epp);
278 int deextend (struct denode *dep, u_long length);
279 int fillinusemap (struct msdosfsmount *pmp);
280 void reinsert (struct denode *dep);
281 int dosdirempty (struct denode *dep);
282 int createde (struct denode *dep, struct denode *ddep, struct denode **depp, struct componentname *cnp);
283 int deupdat (struct denode *dep, int waitfor);
284 int removede (struct denode *pdep, struct denode *dep);
285 int detrunc (struct denode *dep, u_long length, int flags, struct thread *td);
286 int doscheckpath ( struct denode *source, struct denode *target);
287 #endif	/* _KERNEL */
288