master
1/* $NetBSD: denode.h,v 1.29 2021/10/23 16:58:17 thorpej 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#ifndef _MSDOSFS_DENODE_H_
50#define _MSDOSFS_DENODE_H_
51
52#ifndef MAKEFS
53#include <miscfs/genfs/genfs_node.h>
54#else
55struct genfs_node {
56};
57struct vnode;
58struct msdosfsmount;
59struct buf;
60#endif
61
62/*
63 * This is the pc filesystem specific portion of the vnode structure.
64 *
65 * To describe a file uniquely the de_dirclust, de_diroffset, and
66 * de_StartCluster fields are used.
67 *
68 * de_dirclust contains the cluster number of the directory cluster
69 * containing the entry for a file or directory.
70 * de_diroffset is the index into the cluster for the entry describing
71 * a file or directory.
72 * de_StartCluster is the number of the first cluster of the file or directory.
73 *
74 * Now to describe the quirks of the pc filesystem.
75 * - Clusters 0 and 1 are reserved.
76 * - The first allocatable cluster is 2.
77 * - The root directory is of fixed size and all blocks that make it up
78 * are contiguous.
79 * - Cluster 0 refers to the root directory when it is found in the
80 * startcluster field of a directory entry that points to another directory.
81 * - Cluster 0 implies a 0 length file when found in the start cluster field
82 * of a directory entry that points to a file.
83 * - You can't use the cluster number 0 to derive the address of the root
84 * directory.
85 * - Multiple directory entries can point to a directory. The entry in the
86 * parent directory points to a child directory. Any directories in the
87 * child directory contain a ".." entry that points back to the parent.
88 * The child directory itself contains a "." entry that points to itself.
89 * - The root directory does not contain a "." or ".." entry.
90 * - Directory entries for directories are never changed once they are created
91 * (except when removed). The size stays 0, and the last modification time
92 * is never changed. This is because so many directory entries can point to
93 * the physical clusters that make up a directory. It would lead to an
94 * update nightmare.
95 * - The length field in a directory entry pointing to a directory contains 0
96 * (always). The only way to find the end of a directory is to follow the
97 * cluster chain until the "last cluster" marker is found.
98 *
99 * My extensions to make this house of cards work. These apply only to the in
100 * memory copy of the directory entry.
101 * - A reference count for each denode will be kept since dos doesn't keep such
102 * things.
103 */
104
105/*
106 * Internal pseudo-offset for (nonexistent) directory entry for the root
107 * dir in the root dir
108 */
109#define MSDOSFSROOT_OFS 0x1fffffff
110
111/*
112 * The FAT cache structure. fc_fsrcn is the filesystem relative cluster
113 * number that corresponds to the file relative cluster number in this
114 * structure (fc_frcn).
115 */
116struct fatcache {
117 u_long fc_frcn; /* file relative cluster number */
118 u_long fc_fsrcn; /* filesystem relative cluster number */
119};
120
121/*
122 * The FAT entry cache as it stands helps make extending files a "quick"
123 * operation by avoiding having to scan the FAT to discover the last
124 * cluster of the file. The cache also helps sequential reads by
125 * remembering the last cluster read from the file. This also prevents us
126 * from having to rescan the FAT to find the next cluster to read. This
127 * cache is probably pretty worthless if a file is opened by multiple
128 * processes.
129 */
130#define FC_SIZE 3 /* number of entries in the cache */
131#define FC_LASTMAP 0 /* entry the last call to pcbmap() resolved
132 * to */
133#define FC_LASTFC 1 /* entry for the last cluster in the file */
134#define FC_NEXTTOLASTFC 2 /* entry for a close to the last cluster in the file */
135
136#define FCE_EMPTY 0xffffffff /* doesn't represent an actual cluster # */
137
138/*
139 * Set a slot in the FAT cache.
140 */
141#define fc_setcache(dep, slot, frcn, fsrcn) \
142 (dep)->de_fc[slot].fc_frcn = frcn; \
143 (dep)->de_fc[slot].fc_fsrcn = fsrcn;
144
145#define fc_last_to_nexttolast(dep) \
146 do { \
147 (dep)->de_fc[FC_NEXTTOLASTFC].fc_frcn = (dep)->de_fc[FC_LASTFC].fc_frcn; \
148 (dep)->de_fc[FC_NEXTTOLASTFC].fc_fsrcn = (dep)->de_fc[FC_LASTFC].fc_fsrcn; \
149 } while (0)
150
151/*
152 * Auxiliary results from an msdosfs_lookup operation
153 */
154struct msdosfs_lookup_results {
155 u_long mlr_fndoffset; /* offset of found dir entry */
156 int mlr_fndcnt; /* number of slots before de_fndoffset */
157};
158
159/*
160 * This is the in memory variant of a dos directory entry. It is usually
161 * contained within a vnode.
162 */
163struct denode_key {
164 u_long dk_dirclust; /* cluster of the directory file containing this entry */
165 u_long dk_diroffset; /* offset of this entry in the directory cluster */
166 void *dk_dirgen; /* non zero and unique for unlinked nodes */
167};
168struct denode {
169 struct genfs_node de_gnode;
170 struct vnode *de_vnode; /* addr of vnode we are part of */
171 struct vnode *de_devvp; /* vnode of blk dev we live on */
172 u_long de_flag; /* flag bits */
173 dev_t de_dev; /* device where direntry lives */
174 struct denode_key de_key;
175#define de_dirclust de_key.dk_dirclust
176#define de_diroffset de_key.dk_diroffset
177#define de_dirgen de_key.dk_dirgen
178 struct msdosfs_lookup_results de_crap; /* results from lookup */
179 long de_refcnt; /* reference count */
180 struct msdosfsmount *de_pmp; /* addr of our mount struct */
181 struct lockf *de_lockf; /* byte level lock list */
182 u_char de_Name[12]; /* name, from DOS directory entry */
183 u_char de_Attributes; /* attributes, from directory entry */
184 u_char de_CHun; /* Hundredth of second of CTime*/
185 u_short de_CTime; /* creation time */
186 u_short de_CDate; /* creation date */
187 u_short de_ADate; /* access date */
188 u_short de_MTime; /* modification time */
189 u_short de_MDate; /* modification date */
190 u_long de_StartCluster; /* starting cluster of file */
191 u_long de_FileSize; /* size of file in bytes */
192 struct fatcache de_fc[FC_SIZE]; /* FAT cache */
193};
194
195/*
196 * Values for the de_flag field of the denode.
197 */
198#define DE_UPDATE 0x0001 /* Modification time update request. */
199#define DE_CREATE 0x0002 /* Creation time update */
200#define DE_ACCESS 0x0004 /* Access time update */
201#define DE_MODIFIED 0x0008 /* Denode has been modified. */
202#define DE_RENAME 0x0010 /* Denode is in the process of being renamed */
203
204/*
205 * Maximum filename length in Win95
206 * Note: Must be < sizeof(dirent.d_name)
207 */
208#define WIN_MAXLEN 255
209
210/* Maximum size of a file on a FAT filesystem */
211#define MSDOSFS_FILESIZE_MAX 0xFFFFFFFFLL
212
213/*
214 * Transfer directory entries between internal and external form.
215 * dep is a struct denode * (internal form),
216 * dp is a struct direntry * (external form).
217 */
218#define DE_INTERNALIZE32(dep, dp) \
219 ((dep)->de_StartCluster |= getushort((dp)->deHighClust) << 16)
220#define DE_INTERNALIZE(dep, dp) \
221 (memcpy((dep)->de_Name, (dp)->deName, 8), \
222 memcpy((dep)->de_Name+8, (dp)->deExtension, 3),\
223 (dep)->de_Attributes = (dp)->deAttributes, \
224 (dep)->de_CHun = (dp)->deCHundredth, \
225 (dep)->de_CTime = getushort((dp)->deCTime), \
226 (dep)->de_CDate = getushort((dp)->deCDate), \
227 (dep)->de_ADate = getushort((dp)->deADate), \
228 (dep)->de_MTime = getushort((dp)->deMTime), \
229 (dep)->de_MDate = getushort((dp)->deMDate), \
230 (dep)->de_StartCluster = getushort((dp)->deStartCluster), \
231 (dep)->de_FileSize = getulong((dp)->deFileSize), \
232 (FAT32((dep)->de_pmp) ? DE_INTERNALIZE32((dep), (dp)) : 0))
233
234#define DE_EXTERNALIZE32(dp, dep) \
235 putushort((dp)->deHighClust, (dep)->de_StartCluster >> 16)
236#define DE_EXTERNALIZE16(dp, dep) \
237 putushort((dp)->deHighClust, 0)
238#define DE_EXTERNALIZE(dp, dep) \
239 (memcpy((dp)->deName, (dep)->de_Name, 8), \
240 memcpy((dp)->deExtension, (dep)->de_Name+8, 3),\
241 (dp)->deAttributes = (dep)->de_Attributes, \
242 (dp)->deCHundredth = (dep)->de_CHun, \
243 putushort((dp)->deCTime, (dep)->de_CTime), \
244 putushort((dp)->deCDate, (dep)->de_CDate), \
245 putushort((dp)->deADate, (dep)->de_ADate), \
246 putushort((dp)->deMTime, (dep)->de_MTime), \
247 putushort((dp)->deMDate, (dep)->de_MDate), \
248 putushort((dp)->deStartCluster, (dep)->de_StartCluster), \
249 putulong((dp)->deFileSize, \
250 ((dep)->de_Attributes & ATTR_DIRECTORY) ? 0 : (dep)->de_FileSize), \
251 (FAT32((dep)->de_pmp) ? DE_EXTERNALIZE32((dp), (dep)) : DE_EXTERNALIZE16((dp), (dep))))
252
253#define de_forw de_chain[0]
254#define de_back de_chain[1]
255
256#if defined(_KERNEL) || defined(MAKEFS)
257
258#define VTODE(vp) ((struct denode *)(vp)->v_data)
259#define DETOV(de) ((de)->de_vnode)
260
261#define DETIMES(dep, acc, mod, cre, gmtoff) \
262 while ((dep)->de_flag & (DE_UPDATE | DE_CREATE | DE_ACCESS)) \
263 msdosfs_detimes(dep, acc, mod, cre, gmtoff)
264
265/*
266 * This overlays the fid structure (see fstypes.h)
267 */
268struct defid {
269 u_int16_t defid_len; /* length of structure */
270 u_int16_t defid_pad; /* force 4-byte alignment */
271
272 u_int32_t defid_dirclust; /* cluster this dir entry came from */
273 u_int32_t defid_dirofs; /* offset of entry within the cluster */
274 u_int32_t defid_gen; /* generation number */
275};
276
277/*
278 * Prototypes for MSDOSFS vnode operations
279 */
280int msdosfs_lookup (void *);
281int msdosfs_create (void *);
282int msdosfs_close (void *);
283int msdosfs_access (void *);
284int msdosfs_getattr (void *);
285int msdosfs_setattr (void *);
286int msdosfs_read (void *);
287int msdosfs_write (void *);
288int msdosfs_fsync (void *);
289int msdosfs_remove (void *);
290int msdosfs_rename (void *);
291int msdosfs_mkdir (void *);
292int msdosfs_rmdir (void *);
293int msdosfs_readdir (void *);
294int msdosfs_inactive (void *);
295int msdosfs_reclaim (void *);
296int msdosfs_bmap (void *);
297int msdosfs_strategy (void *);
298int msdosfs_print (void *);
299int msdosfs_advlock (void *);
300int msdosfs_pathconf (void *);
301
302/*
303 * Internal service routine prototypes.
304 */
305struct componentname;
306struct direntry;
307struct kauth_cred;
308int msdosfs_update(struct vnode *, const struct timespec *,
309 const struct timespec *, int);
310int msdosfs_createde(struct denode *, struct denode *,
311 const struct msdosfs_lookup_results *,
312 struct denode **, struct componentname *);
313int msdosfs_deextend(struct denode *, u_long, struct kauth_cred *);
314#ifdef MAKEFS
315int msdosfs_deget(struct msdosfsmount *, u_long, u_long, struct denode **);
316#else
317int msdosfs_deget(struct msdosfsmount *, u_long, u_long, struct vnode **);
318#endif
319int msdosfs_detrunc(struct denode *, u_long, int, struct kauth_cred *);
320int msdosfs_deupdat(struct denode *, int);
321int msdosfs_dosdirempty(struct denode *);
322int msdosfs_readde(struct denode *, struct buf **, struct direntry **);
323int msdosfs_readep(struct msdosfsmount *, u_long, u_long,
324 struct buf **, struct direntry **);
325int msdosfs_removede(struct denode *, struct denode *,
326 const struct msdosfs_lookup_results *);
327int msdosfs_uniqdosname(struct denode *, struct componentname *, u_char *);
328int msdosfs_findwin95(struct denode *);
329int msdosfs_gop_alloc(struct vnode *, off_t, off_t, int,
330 struct kauth_cred *);
331void msdosfs_gop_markupdate(struct vnode *, int);
332void msdosfs_detimes(struct denode *, const struct timespec *,
333 const struct timespec *, const struct timespec *, int);
334int msdosfs_fh_enter(struct msdosfsmount *, uint32_t, uint32_t, uint32_t *);
335int msdosfs_fh_remove(struct msdosfsmount *, uint32_t, uint32_t);
336int msdosfs_fh_lookup(struct msdosfsmount *, uint32_t, uint32_t,
337 uint32_t *);
338void msdosfs_fh_destroy(struct msdosfsmount *);
339#endif /* _KERNEL || MAKEFS */
340#endif /* _MSDOSFS_DENODE_H_ */