denode.h (12365B) - Raw
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 */ 108 struct 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 */ 142 struct 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(MAKEFS) 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 */ 257 struct 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 }; 267 268 extern struct vop_vector msdosfs_vnodeops; 269 270 #ifdef _KERNEL 271 int msdosfs_lookup(struct vop_cachedlookup_args *); 272 int msdosfs_inactive(struct vop_inactive_args *); 273 int msdosfs_reclaim(struct vop_reclaim_args *); 274 int 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 */ 281 struct componentname; 282 int deget(struct msdosfsmount *, u_long, u_long, int, struct denode **); 283 int uniqdosname(struct denode *, struct componentname *, u_char *); 284 285 int readep(struct msdosfsmount *pmp, u_long dirclu, u_long dirofs, struct buf **bpp, struct direntry **epp); 286 int readde(struct denode *dep, struct buf **bpp, struct direntry **epp); 287 int deextend(struct denode *dep, u_long length, struct ucred *cred); 288 int fillinusemap(struct msdosfsmount *pmp); 289 void reinsert(struct denode *dep); 290 int dosdirempty(struct denode *dep); 291 int createde(struct denode *dep, struct denode *ddep, struct denode **depp, struct componentname *cnp); 292 int deupdat(struct denode *dep, int waitfor); 293 int removede(struct denode *pdep, struct denode *dep); 294 int detrunc(struct denode *dep, u_long length, int flags, struct ucred *cred); 295 int doscheckpath( struct denode *source, struct denode *target, 296 daddr_t *wait_scn); 297 #endif /* _KERNEL || MAKEFS */ 298 #endif /* !_FS_MSDOSFS_DENODE_H_ */