Annotation of sys/msdosfs/denode.h, Revision 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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