Annotation of sys/msdosfs/denode.h, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: denode.h,v 1.21 2007/06/02 02:04:21 deraadt Exp $ */
2: /* $NetBSD: denode.h,v 1.24 1997/10/17 11:23:39 ws Exp $ */
3:
4: /*-
5: * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
6: * Copyright (C) 1994, 1995, 1997 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: * This is the pc filesystem specific portion of the vnode structure.
53: *
54: * To describe a file uniquely the de_dirclust, de_diroffset, and
55: * de_StartCluster fields are used.
56: *
57: * de_dirclust contains the cluster number of the directory cluster
58: * containing the entry for a file or directory.
59: * de_diroffset is the index into the cluster for the entry describing
60: * a file or directory.
61: * de_StartCluster is the number of the first cluster of the file or directory.
62: *
63: * Now to describe the quirks of the pc filesystem.
64: * - Clusters 0 and 1 are reserved.
65: * - The first allocatable cluster is 2.
66: * - The root directory is of fixed size and all blocks that make it up
67: * are contiguous.
68: * - Cluster 0 refers to the root directory when it is found in the
69: * startcluster field of a directory entry that points to another directory.
70: * - Cluster 0 implies a 0 length file when found in the start cluster field
71: * of a directory entry that points to a file.
72: * - You can't use the cluster number 0 to derive the address of the root
73: * directory.
74: * - Multiple directory entries can point to a directory. The entry in the
75: * parent directory points to a child directory. Any directories in the
76: * child directory contain a ".." entry that points back to the parent.
77: * The child directory itself contains a "." entry that points to itself.
78: * - The root directory does not contain a "." or ".." entry.
79: * - Directory entries for directories are never changed once they are created
80: * (except when removed). The size stays 0, and the last modification time
81: * is never changed. This is because so many directory entries can point to
82: * the physical clusters that make up a directory. It would lead to an
83: * update nightmare.
84: * - The length field in a directory entry pointing to a directory contains 0
85: * (always). The only way to find the end of a directory is to follow the
86: * cluster chain until the "last cluster" marker is found.
87: *
88: * My extensions to make this house of cards work. These apply only to the in
89: * memory copy of the directory entry.
90: * - A reference count for each denode will be kept since dos doesn't keep such
91: * things.
92: */
93:
94: /*
95: * Internal pseudo-offset for (nonexistent) directory entry for the root
96: * dir in the root dir
97: */
98: #define MSDOSFSROOT_OFS 0x1fffffff
99:
100: /*
101: * The fat cache structure. fc_fsrcn is the filesystem relative cluster
102: * number that corresponds to the file relative cluster number in this
103: * structure (fc_frcn).
104: */
105: struct fatcache {
106: uint32_t fc_frcn; /* file relative cluster number */
107: uint32_t fc_fsrcn; /* filesystem relative cluster number */
108: };
109:
110: /*
111: * The fat entry cache as it stands helps make extending files a "quick"
112: * operation by avoiding having to scan the fat to discover the last
113: * cluster of the file. The cache also helps sequential reads by
114: * remembering the last cluster read from the file. This also prevents us
115: * from having to rescan the fat to find the next cluster to read. This
116: * cache is probably pretty worthless if a file is opened by multiple
117: * processes.
118: */
119: #define FC_SIZE 2 /* number of entries in the cache */
120: #define FC_LASTMAP 0 /* entry the last call to pcbmap() resolved
121: * to */
122: #define FC_LASTFC 1 /* entry for the last cluster in the file */
123:
124: #define FCE_EMPTY 0xffffffff /* doesn't represent an actual cluster # */
125:
126: /*
127: * Set a slot in the fat cache.
128: */
129: #define fc_setcache(dep, slot, frcn, fsrcn) \
130: (dep)->de_fc[slot].fc_frcn = frcn; \
131: (dep)->de_fc[slot].fc_fsrcn = fsrcn;
132:
133: /*
134: * This is the in memory variant of a dos directory entry. It is usually
135: * contained within a vnode.
136: */
137: struct denode {
138: struct denode *de_next; /* Hash chain forward */
139: struct denode **de_prev; /* Hash chain back */
140: struct vnode *de_vnode; /* addr of vnode we are part of */
141: struct vnode *de_devvp; /* vnode of blk dev we live on */
142: uint32_t de_flag; /* flag bits */
143: dev_t de_dev; /* device where direntry lives */
144: daddr64_t de_lastr;
145: uint32_t de_dirclust; /* cluster of the directory file containing this entry */
146: uint32_t de_diroffset; /* offset of this entry in the directory cluster */
147: uint32_t 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: struct lock de_lock; /* denode lock */
153: u_char de_Name[12]; /* name, from DOS directory entry */
154: u_char de_Attributes; /* attributes, from directory entry */
155: u_char de_CTimeHundredth; /* creation time, 1/100th of a sec */
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: uint32_t de_StartCluster; /* starting cluster of file */
162: uint32_t de_FileSize; /* size of file in bytes */
163: struct fatcache de_fc[FC_SIZE]; /* fat cache */
164: };
165:
166: /*
167: * Values for the de_flag field of the denode.
168: */
169: #define DE_UPDATE 0x0004 /* Modification time update request. */
170: #define DE_CREATE 0x0008 /* Creation time update */
171: #define DE_ACCESS 0x0010 /* Access time update */
172: #define DE_MODIFIED 0x0020 /* Denode has been modified. */
173: #define DE_RENAME 0x0040 /* Denode is in the process of being renamed */
174:
175: /*
176: * Maximum filename length in Win95
177: * Note: Must be < sizeof(dirent.d_name)
178: */
179: #define WIN_MAXLEN 255
180:
181: /* Maximum size of a file on a FAT filesystem */
182: #define MSDOSFS_FILESIZE_MAX 0xFFFFFFFFLL
183:
184: /*
185: * Transfer directory entries between internal and external form.
186: * dep is a struct denode * (internal form),
187: * dp is a struct direntry * (external form).
188: */
189: #define DE_INTERNALIZE32(dep, dp) \
190: ((dep)->de_StartCluster |= getushort((dp)->deHighClust) << 16)
191: #define DE_INTERNALIZE(dep, dp) \
192: (bcopy((dp)->deName, (dep)->de_Name, 11), \
193: (dep)->de_Attributes = (dp)->deAttributes, \
194: (dep)->de_CTimeHundredth = (dp)->deCTimeHundredth, \
195: (dep)->de_CTime = getushort((dp)->deCTime), \
196: (dep)->de_CDate = getushort((dp)->deCDate), \
197: (dep)->de_ADate = getushort((dp)->deADate), \
198: (dep)->de_MTime = getushort((dp)->deMTime), \
199: (dep)->de_MDate = getushort((dp)->deMDate), \
200: (dep)->de_StartCluster = getushort((dp)->deStartCluster), \
201: (dep)->de_FileSize = getulong((dp)->deFileSize), \
202: (FAT32((dep)->de_pmp) ? DE_INTERNALIZE32((dep), (dp)) : 0))
203:
204: #define DE_EXTERNALIZE(dp, dep) \
205: (bcopy((dep)->de_Name, (dp)->deName, 11), \
206: (dp)->deAttributes = (dep)->de_Attributes, \
207: (dp)->deLowerCase = CASE_LOWER_BASE | CASE_LOWER_EXT, \
208: (dp)->deCTimeHundredth = (dep)->de_CTimeHundredth, \
209: putushort((dp)->deCTime, (dep)->de_CTime), \
210: putushort((dp)->deCDate, (dep)->de_CDate), \
211: putushort((dp)->deADate, (dep)->de_ADate), \
212: putushort((dp)->deMTime, (dep)->de_MTime), \
213: putushort((dp)->deMDate, (dep)->de_MDate), \
214: putushort((dp)->deStartCluster, (dep)->de_StartCluster), \
215: putulong((dp)->deFileSize, \
216: ((dep)->de_Attributes & ATTR_DIRECTORY) ? 0 : (dep)->de_FileSize),\
217: putushort((dp)->deHighClust, \
218: FAT32((dep)->de_pmp) ? (dep)->de_StartCluster >> 16 : 0))
219:
220: #define de_forw de_chain[0]
221: #define de_back de_chain[1]
222:
223: #ifdef _KERNEL
224:
225: #define VTODE(vp) ((struct denode *)(vp)->v_data)
226: #define DETOV(de) ((de)->de_vnode)
227:
228: #define DETIMES(dep, acc, mod, cre) \
229: if ((dep)->de_flag & (DE_UPDATE | DE_CREATE | DE_ACCESS)) { \
230: (dep)->de_flag |= DE_MODIFIED; \
231: if ((dep)->de_flag & DE_UPDATE) { \
232: unix2dostime((mod), &(dep)->de_MDate, &(dep)->de_MTime, NULL); \
233: (dep)->de_Attributes |= ATTR_ARCHIVE; \
234: } \
235: if (!((dep)->de_pmp->pm_flags & MSDOSFSMNT_NOWIN95)) { \
236: if ((dep)->de_flag & DE_ACCESS) \
237: unix2dostime((acc), &(dep)->de_ADate, NULL, NULL); \
238: if ((dep)->de_flag & DE_CREATE) \
239: unix2dostime((cre), &(dep)->de_CDate, &(dep)->de_CTime, &(dep)->de_CTimeHundredth); \
240: } \
241: (dep)->de_flag &= ~(DE_UPDATE | DE_CREATE | DE_ACCESS); \
242: }
243:
244: /*
245: * This overlays the fid structure (see mount.h)
246: */
247: struct defid {
248: u_short defid_len; /* length of structure */
249: u_short defid_pad; /* force long alignment */
250:
251: uint32_t defid_dirclust; /* cluster this dir entry came from */
252: uint32_t defid_dirofs; /* offset of entry within the cluster */
253: #if 0
254: uint32_t defid_gen; /* generation number */
255: #endif
256: };
257:
258: /*
259: * Prototypes for MSDOSFS vnode operations
260: */
261: int msdosfs_lookup(void *);
262: int msdosfs_create(void *);
263: int msdosfs_mknod(void *);
264: int msdosfs_open(void *);
265: int msdosfs_close(void *);
266: int msdosfs_access(void *);
267: int msdosfs_getattr(void *);
268: int msdosfs_setattr(void *);
269: int msdosfs_read(void *);
270: int msdosfs_write(void *);
271: int msdosfs_ioctl(void *);
272: int msdosfs_poll(void *);
273: int msdosfs_fsync(void *);
274: int msdosfs_remove(void *);
275: int msdosfs_link(void *);
276: int msdosfs_rename(void *);
277: int msdosfs_mkdir(void *);
278: int msdosfs_rmdir(void *);
279: int msdosfs_symlink(void *);
280: int msdosfs_readdir(void *);
281: int msdosfs_readlink(void *);
282: int msdosfs_inactive(void *);
283: int msdosfs_reclaim(void *);
284: int msdosfs_lock(void *);
285: int msdosfs_unlock(void *);
286: int msdosfs_bmap(void *);
287: int msdosfs_strategy(void *);
288: int msdosfs_print(void *);
289: int msdosfs_islocked(void *);
290: int msdosfs_advlock(void *);
291: int msdosfs_pathconf(void *);
292:
293: /*
294: * Internal service routine prototypes.
295: */
296: int createde(struct denode *, struct denode *, struct denode **, struct componentname *);
297: int deextend(struct denode *, uint32_t, struct ucred *);
298: int deget(struct msdosfsmount *, uint32_t, uint32_t, struct denode **);
299: int detrunc(struct denode *, uint32_t, int, struct ucred *, struct proc *);
300: int deupdat(struct denode *, int);
301: int doscheckpath(struct denode *, struct denode *);
302: int dosdirempty(struct denode *);
303: int readde(struct denode *, struct buf **, struct direntry **);
304: int readep(struct msdosfsmount *, uint32_t, uint32_t, struct buf **, struct direntry **);
305: void reinsert(struct denode *);
306: int removede(struct denode *, struct denode *);
307: int uniqdosname(struct denode *, struct componentname *, u_char *);
308: int findwin95(struct denode *);
309: #endif /* _KERNEL */
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