1/* $NetBSD: denode.h,v 1.25 1997/11/17 15:36:28 ws Exp $ */
2
3/*-
4 * SPDX-License-Identifier: BSD-4-Clause
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#ifndef _FS_MSDOSFS_DENODE_H_
52#define _FS_MSDOSFS_DENODE_H_
53
54/*
55 * This is the pc filesystem specific portion of the vnode structure.
56 *
57 * To describe a file uniquely the de_dirclust, de_diroffset, and
58 * de_StartCluster fields are used.
59 *
60 * de_dirclust contains the cluster number of the directory cluster
61 * containing the entry for a file or directory.
62 * de_diroffset is the index into the cluster for the entry describing
63 * a file or directory.
64 * de_StartCluster is the number of the first cluster of the file or directory.
65 *
66 * Now to describe the quirks of the pc filesystem.
67 * - Clusters 0 and 1 are reserved.
68 * - The first allocatable cluster is 2.
69 * - The root directory is of fixed size and all blocks that make it up
70 * are contiguous.
71 * - Cluster 0 refers to the root directory when it is found in the
72 * startcluster field of a directory entry that points to another directory.
73 * - Cluster 0 implies a 0 length file when found in the start cluster field
74 * of a directory entry that points to a file.
75 * - You can't use the cluster number 0 to derive the address of the root
76 * directory.
77 * - Multiple directory entries can point to a directory. The entry in the
78 * parent directory points to a child directory. Any directories in the
79 * child directory contain a ".." entry that points back to the parent.
80 * The child directory itself contains a "." entry that points to itself.
81 * - The root directory does not contain a "." or ".." entry.
82 * - Directory entries for directories are never changed once they are created
83 * (except when removed). The size stays 0, and the last modification time
84 * is never changed. This is because so many directory entries can point to
85 * the physical clusters that make up a directory. It would lead to an
86 * update nightmare.
87 * - The length field in a directory entry pointing to a directory contains 0
88 * (always). The only way to find the end of a directory is to follow the
89 * cluster chain until the "last cluster" marker is found.
90 *
91 * My extensions to make this house of cards work. These apply only to the in
92 * memory copy of the directory entry.
93 * - A reference count for each denode will be kept since dos doesn't keep such
94 * things.
95 */
96
97/*
98 * Internal pseudo-offset for (nonexistent) directory entry for the root
99 * dir in the root dir
100 */
101#define MSDOSFSROOT_OFS 0x1fffffff
102
103/*
104 * The FAT cache structure. fc_fsrcn is the filesystem relative cluster
105 * number that corresponds to the file relative cluster number in this
106 * structure (fc_frcn).
107 */
108struct fatcache {
109 u_long fc_frcn; /* file relative cluster number */
110 u_long fc_fsrcn; /* filesystem relative cluster number */
111};
112
113/*
114 * The FAT entry cache as it stands helps make extending files a "quick"
115 * operation by avoiding having to scan the FAT to discover the last
116 * cluster of the file. The cache also helps sequential reads by
117 * remembering the last cluster read from the file. This also prevents us
118 * from having to rescan the FAT to find the next cluster to read. This
119 * cache is probably pretty worthless if a file is opened by multiple
120 * processes.
121 */
122#define FC_SIZE 3 /* number of entries in the cache */
123#define FC_LASTMAP 0 /* entry the last call to pcbmap() resolved
124 * to */
125#define FC_LASTFC 1 /* entry for the last cluster in the file */
126#define FC_NEXTTOLASTFC 2 /* entry for a close to the last cluster in
127 * the file */
128
129#define FCE_EMPTY 0xffffffff /* doesn't represent an actual cluster # */
130
131/*
132 * Set a slot in the FAT cache.
133 */
134#define fc_setcache(dep, slot, frcn, fsrcn) \
135 (dep)->de_fc[(slot)].fc_frcn = (frcn); \
136 (dep)->de_fc[(slot)].fc_fsrcn = (fsrcn);
137
138/*
139 * This is the in memory variant of a dos directory entry. It is usually
140 * contained within a vnode.
141 */
142struct denode {
143 struct vnode *de_vnode; /* addr of vnode we are part of */
144 struct vn_clusterw de_clusterw; /* buffer clustering information */
145 u_long de_flag; /* flag bits */
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 uint64_t de_inode; /* Inode number (really index of DOS style direntry) */
166};
167
168/*
169 * Values for the de_flag field of the denode.
170 */
171#define DE_UPDATE 0x0004 /* Modification time update request */
172#define DE_CREATE 0x0008 /* Creation time update */
173#define DE_ACCESS 0x0010 /* Access time update */
174#define DE_MODIFIED 0x0020 /* Denode has been modified */
175
176/* Maximum size of a file on a FAT filesystem */
177#define MSDOSFS_FILESIZE_MAX 0xFFFFFFFFLL
178
179/*
180 * Transfer directory entries between internal and external form.
181 * dep is a struct denode * (internal form),
182 * dp is a struct direntry * (external form).
183 */
184#define DE_INTERNALIZE32(dep, dp) \
185 ((dep)->de_StartCluster |= getushort((dp)->deHighClust) << 16)
186#define DE_INTERNALIZE(dep, dp) \
187 (memcpy((dep)->de_Name, (dp)->deName, 11), \
188 (dep)->de_Attributes = (dp)->deAttributes, \
189 (dep)->de_LowerCase = (dp)->deLowerCase, \
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_EXTERNALIZE(dp, dep) \
201 (memcpy((dp)->deName, (dep)->de_Name, 11), \
202 (dp)->deAttributes = (dep)->de_Attributes, \
203 (dp)->deLowerCase = (dep)->de_LowerCase, \
204 (dp)->deCHundredth = (dep)->de_CHun, \
205 putushort((dp)->deCTime, (dep)->de_CTime), \
206 putushort((dp)->deCDate, (dep)->de_CDate), \
207 putushort((dp)->deADate, (dep)->de_ADate), \
208 putushort((dp)->deMTime, (dep)->de_MTime), \
209 putushort((dp)->deMDate, (dep)->de_MDate), \
210 putushort((dp)->deStartCluster, (dep)->de_StartCluster), \
211 putulong((dp)->deFileSize, \
212 ((dep)->de_Attributes & ATTR_DIRECTORY) ? 0 : (dep)->de_FileSize), \
213 putushort((dp)->deHighClust, (dep)->de_StartCluster >> 16))
214
215#if defined(_KERNEL) || defined(_WANT_MSDOSFS_INTERNALS)
216
217#define VTODE(vp) ((struct denode *)(vp)->v_data)
218#define DETOV(de) ((de)->de_vnode)
219
220#define DETOI(pmp, cn, off) \
221 ((cn) == MSDOSFSROOT \
222 ? (((uint64_t)(off) >> 5)) \
223 : (((((uint64_t)pmp->pm_bpcluster * ((cn) - 2) + (off))) >> 5) \
224 + pmp->pm_RootDirEnts))
225
226#define DETIMES(dep, acc, mod, cre) do { \
227 if ((dep)->de_flag & DE_UPDATE) { \
228 (dep)->de_flag |= DE_MODIFIED; \
229 timespec2fattime((mod), 0, &(dep)->de_MDate, \
230 &(dep)->de_MTime, NULL); \
231 (dep)->de_Attributes |= ATTR_ARCHIVE; \
232 } \
233 if ((dep)->de_pmp->pm_flags & MSDOSFSMNT_NOWIN95) { \
234 (dep)->de_flag &= ~(DE_UPDATE | DE_CREATE | DE_ACCESS); \
235 break; \
236 } \
237 if ((dep)->de_flag & DE_ACCESS) { \
238 uint16_t adate; \
239 \
240 timespec2fattime((acc), 0, &adate, NULL, NULL); \
241 if (adate != (dep)->de_ADate) { \
242 (dep)->de_flag |= DE_MODIFIED; \
243 (dep)->de_ADate = adate; \
244 } \
245 } \
246 if ((dep)->de_flag & DE_CREATE) { \
247 timespec2fattime((cre), 0, &(dep)->de_CDate, \
248 &(dep)->de_CTime, &(dep)->de_CHun); \
249 (dep)->de_flag |= DE_MODIFIED; \
250 } \
251 (dep)->de_flag &= ~(DE_UPDATE | DE_CREATE | DE_ACCESS); \
252} while (0)
253
254/*
255 * This overlays the fid structure (see mount.h)
256 */
257struct defid {
258 u_short defid_len; /* length of structure */
259 u_short defid_pad; /* force long alignment */
260
261 uint32_t defid_dirclust; /* cluster this dir entry came from */
262 uint32_t defid_dirofs; /* offset of entry within the cluster */
263#if 0
264 uint32_t defid_gen; /* generation number */
265#endif
266};
267
268extern struct vop_vector msdosfs_vnodeops;
269
270#ifdef _KERNEL
271int msdosfs_lookup(struct vop_cachedlookup_args *);
272int msdosfs_inactive(struct vop_inactive_args *);
273int msdosfs_reclaim(struct vop_reclaim_args *);
274int msdosfs_lookup_ino(struct vnode *vdp, struct vnode **vpp,
275 struct componentname *cnp, daddr_t *scnp, u_long *blkoffp);
276#endif
277
278/*
279 * Internal service routine prototypes.
280 */
281struct componentname;
282int deget(struct msdosfsmount *, u_long, u_long, int, struct denode **);
283int uniqdosname(struct denode *, struct componentname *, u_char *);
284
285int readep(struct msdosfsmount *pmp, u_long dirclu, u_long dirofs, struct buf **bpp, struct direntry **epp);
286int readde(struct denode *dep, struct buf **bpp, struct direntry **epp);
287int deextend(struct denode *dep, u_long length, struct ucred *cred);
288int fillinusemap(struct msdosfsmount *pmp);
289void reinsert(struct denode *dep);
290int dosdirempty(struct denode *dep);
291int createde(struct denode *dep, struct denode *ddep, struct denode **depp, struct componentname *cnp);
292int deupdat(struct denode *dep, int waitfor);
293int removede(struct denode *pdep, struct denode *dep);
294int detrunc(struct denode *dep, u_long length, int flags, struct ucred *cred);
295int doscheckpath( struct denode *source, struct denode *target,
296 daddr_t *wait_scn);
297#endif /* _KERNEL || _WANT_MSDOSFS_INTERNALS */
298#endif /* !_FS_MSDOSFS_DENODE_H_ */