sys/fs/msdosfs/denode.h

   1 /*      $NetBSD: denode.h,v 1.24 2014/07/08 09:21:52 hannken 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
  55 struct genfs_node {
  56 };
  57 struct vnode;
  58 struct msdosfsmount;
  59 struct 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  */
 116 struct 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 /*
 153  * This is the in memory variant of a dos directory entry.  It is usually
 154  * contained within a vnode.
 155  */
 156 struct denode_key {
 157         u_long dk_dirclust;     /* cluster of the directory file containing this entry */
 158         u_long dk_diroffset;    /* offset of this entry in the directory cluster */
 159         void *dk_dirgen;        /* non zero and unique for unlinked nodes */
 160 };
 161 struct denode {
 162         struct genfs_node de_gnode;
 163         struct vnode *de_vnode; /* addr of vnode we are part of */
 164         struct vnode *de_devvp; /* vnode of blk dev we live on */
 165         u_long de_flag;         /* flag bits */
 166         dev_t de_dev;           /* device where direntry lives */
 167         struct denode_key de_key;
 168 #define de_dirclust de_key.dk_dirclust
 169 #define de_diroffset de_key.dk_diroffset
 170 #define de_dirgen de_key.dk_dirgen
 171         u_long de_fndoffset;    /* offset of found dir entry */
 172         int de_fndcnt;          /* number of slots before de_fndoffset */
 173         long de_refcnt;         /* reference count */
 174         struct msdosfsmount *de_pmp;    /* addr of our mount struct */
 175         struct lockf *de_lockf; /* byte level lock list */
 176         u_char de_Name[12];     /* name, from DOS directory entry */
 177         u_char de_Attributes;   /* attributes, from directory entry */
 178         u_char de_CHun;         /* Hundredth of second of CTime*/
 179         u_short de_CTime;       /* creation time */
 180         u_short de_CDate;       /* creation date */
 181         u_short de_ADate;       /* access date */
 182         u_short de_MTime;       /* modification time */
 183         u_short de_MDate;       /* modification date */
 184         u_long de_StartCluster; /* starting cluster of file */
 185         u_long de_FileSize;     /* size of file in bytes */
 186         struct fatcache de_fc[FC_SIZE]; /* FAT cache */
 187 };
 188
 189 /*
 190  * Values for the de_flag field of the denode.
 191  */
 192 #define DE_UPDATE       0x0001  /* Modification time update request. */
 193 #define DE_CREATE       0x0002  /* Creation time update */
 194 #define DE_ACCESS       0x0004  /* Access time update */
 195 #define DE_MODIFIED     0x0008  /* Denode has been modified. */
 196 #define DE_RENAME       0x0010  /* Denode is in the process of being renamed */
 197
 198 /*
 199  * Maximum filename length in Win95
 200  * Note: Must be < sizeof(dirent.d_name)
 201  */
 202 #define WIN_MAXLEN      255
 203
 204 /* Maximum size of a file on a FAT filesystem */
 205 #define MSDOSFS_FILESIZE_MAX    0xFFFFFFFFLL
 206
 207 /*
 208  * Transfer directory entries between internal and external form.
 209  * dep is a struct denode * (internal form),
 210  * dp is a struct direntry * (external form).
 211  */
 212 #define DE_INTERNALIZE32(dep, dp)                       \
 213          ((dep)->de_StartCluster |= getushort((dp)->deHighClust) << 16)
 214 #define DE_INTERNALIZE(dep, dp)                         \
 215         (memcpy((dep)->de_Name, (dp)->deName, 11),      \
 216          (dep)->de_Attributes = (dp)->deAttributes,     \
 217          (dep)->de_CHun = (dp)->deCHundredth,           \
 218          (dep)->de_CTime = getushort((dp)->deCTime),    \
 219          (dep)->de_CDate = getushort((dp)->deCDate),    \
 220          (dep)->de_ADate = getushort((dp)->deADate),    \
 221          (dep)->de_MTime = getushort((dp)->deMTime),    \
 222          (dep)->de_MDate = getushort((dp)->deMDate),    \
 223          (dep)->de_StartCluster = getushort((dp)->deStartCluster), \
 224          (dep)->de_FileSize = getulong((dp)->deFileSize), \
 225          (FAT32((dep)->de_pmp) ? DE_INTERNALIZE32((dep), (dp)) : 0))
 226
 227 #define DE_EXTERNALIZE32(dp, dep)                       \
 228          putushort((dp)->deHighClust, (dep)->de_StartCluster >> 16)
 229 #define DE_EXTERNALIZE16(dp, dep)                       \
 230          putushort((dp)->deHighClust, 0)
 231 #define DE_EXTERNALIZE(dp, dep)                         \
 232         (memcpy((dp)->deName, (dep)->de_Name, 11),      \
 233          (dp)->deAttributes = (dep)->de_Attributes,     \
 234          (dp)->deCHundredth = (dep)->de_CHun,           \
 235          putushort((dp)->deCTime, (dep)->de_CTime),     \
 236          putushort((dp)->deCDate, (dep)->de_CDate),     \
 237          putushort((dp)->deADate, (dep)->de_ADate),     \
 238          putushort((dp)->deMTime, (dep)->de_MTime),     \
 239          putushort((dp)->deMDate, (dep)->de_MDate),     \
 240          putushort((dp)->deStartCluster, (dep)->de_StartCluster), \
 241          putulong((dp)->deFileSize,                     \
 242              ((dep)->de_Attributes & ATTR_DIRECTORY) ? 0 : (dep)->de_FileSize), \
 243          (FAT32((dep)->de_pmp) ? DE_EXTERNALIZE32((dp), (dep)) : DE_EXTERNALIZE16((dp), (dep))))
 244
 245 #define de_forw         de_chain[0]
 246 #define de_back         de_chain[1]
 247
 248 #if defined(_KERNEL) || defined(MAKEFS)
 249
 250 #define VTODE(vp)       ((struct denode *)(vp)->v_data)
 251 #define DETOV(de)       ((de)->de_vnode)
 252
 253 #define DETIMES(dep, acc, mod, cre, gmtoff) \
 254         while ((dep)->de_flag & (DE_UPDATE | DE_CREATE | DE_ACCESS)) \
 255                 msdosfs_detimes(dep, acc, mod, cre, gmtoff)
 256
 257 /*
 258  * This overlays the fid structure (see fstypes.h)
 259  */
 260 struct defid {
 261         u_int16_t defid_len;    /* length of structure */
 262         u_int16_t defid_pad;    /* force 4-byte alignment */
 263
 264         u_int32_t defid_dirclust; /* cluster this dir entry came from */
 265         u_int32_t defid_dirofs; /* offset of entry within the cluster */
 266         u_int32_t defid_gen;    /* generation number */
 267 };
 268
 269 /*
 270  * Prototypes for MSDOSFS vnode operations
 271  */
 272 int     msdosfs_lookup          (void *);
 273 int     msdosfs_create          (void *);
 274 int     msdosfs_close           (void *);
 275 int     msdosfs_access          (void *);
 276 int     msdosfs_getattr         (void *);
 277 int     msdosfs_setattr         (void *);
 278 int     msdosfs_read            (void *);
 279 int     msdosfs_write           (void *);
 280 #define msdosfs_lease_check     genfs_lease_check
 281 #define msdosfs_ioctl           genfs_enoioctl
 282 #define msdosfs_poll            genfs_poll
 283 #define msdosfs_revoke          genfs_revoke
 284 #define msdosfs_mmap            genfs_mmap
 285 int     msdosfs_fsync           (void *);
 286 #define msdosfs_seek            genfs_seek
 287 int     msdosfs_remove          (void *);
 288 int     msdosfs_rename          (void *);
 289 int     msdosfs_mkdir           (void *);
 290 int     msdosfs_rmdir           (void *);
 291 int     msdosfs_readdir         (void *);
 292 #define msdosfs_abortop         genfs_abortop
 293 int     msdosfs_inactive        (void *);
 294 int     msdosfs_reclaim         (void *);
 295 int     msdosfs_bmap            (void *);
 296 int     msdosfs_strategy        (void *);
 297 int     msdosfs_print           (void *);
 298 int     msdosfs_advlock         (void *);
 299 int     msdosfs_pathconf        (void *);
 300
 301 /*
 302  * Internal service routine prototypes.
 303  */
 304 struct componentname;
 305 struct direntry;
 306 struct kauth_cred;
 307 int msdosfs_update(struct vnode *, const struct timespec *,
 308             const struct timespec *, int);
 309 int createde(struct denode *, struct denode *,
 310                 struct denode **, struct componentname *);
 311 int deextend(struct denode *, u_long, struct kauth_cred *);
 312 #ifdef MAKEFS
 313 int deget(struct msdosfsmount *, u_long, u_long, struct denode **);
 314 #else
 315 int deget(struct msdosfsmount *, u_long, u_long, struct vnode **);
 316 #endif
 317 int detrunc(struct denode *, u_long, int, struct kauth_cred *);
 318 int deupdat(struct denode *, int);
 319 int doscheckpath(struct denode *, struct denode *);
 320 int dosdirempty(struct denode *);
 321 int readde(struct denode *, struct buf **, struct direntry **);
 322 int readep(struct msdosfsmount *, u_long, u_long,
 323                 struct buf **, struct direntry **);
 324 int removede(struct denode *, struct denode *);
 325 int uniqdosname(struct denode *, struct componentname *, u_char *);
 326 int findwin95(struct denode *);
 327 int msdosfs_gop_alloc(struct vnode *, off_t, off_t, int, struct kauth_cred *);
 328 void msdosfs_gop_markupdate(struct vnode *, int);
 329 void msdosfs_detimes(struct denode *, const struct timespec *,
 330     const struct timespec *, const struct timespec *, int);
 331 int msdosfs_fh_enter(struct msdosfsmount *, uint32_t, uint32_t, uint32_t *);
 332 int msdosfs_fh_remove(struct msdosfsmount *, uint32_t, uint32_t);
 333 int msdosfs_fh_lookup(struct msdosfsmount *, uint32_t, uint32_t, uint32_t *);
 334 void msdosfs_fh_destroy(struct msdosfsmount *);
 335 #endif  /* _KERNEL || MAKEFS */
 336 #endif /* _MSDOSFS_DENODE_H_ */