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/* $Id: denode.h,v 1.11 1997/02/22 09:40:44 peter Exp $ */
/* $NetBSD: denode.h,v 1.8 1994/08/21 18:43:49 ws Exp $ */
/*-
* Copyright (C) 1994 Wolfgang Solfrank.
* Copyright (C) 1994 TooLs GmbH.
* All rights reserved.
* Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Written by Paul Popelka (paulp@uts.amdahl.com)
*
* You can do anything you want with this software, just don't say you wrote
* it, and don't remove this notice.
*
* This software is provided "as is".
*
* The author supplies this software to be publicly redistributed on the
* understanding that the author is not responsible for the correct
* functioning of this software in any circumstances and is not liable for
* any damages caused by this software.
*
* October 1992
*/
/*
* This is the pc filesystem specific portion of the vnode structure.
*
* To describe a file uniquely the de_dirclust, de_diroffset, and
* de_StartCluster fields are used.
*
* de_dirclust contains the cluster number of the directory cluster
* containing the entry for a file or directory.
* de_diroffset is the index into the cluster for the entry describing
* a file or directory.
* de_StartCluster is the number of the first cluster of the file or directory.
*
* Now to describe the quirks of the pc filesystem.
* - Clusters 0 and 1 are reserved.
* - The first allocatable cluster is 2.
* - The root directory is of fixed size and all blocks that make it up
* are contiguous.
* - Cluster 0 refers to the root directory when it is found in the
* startcluster field of a directory entry that points to another directory.
* - Cluster 0 implies a 0 length file when found in the start cluster field
* of a directory entry that points to a file.
* - You can't use the cluster number 0 to derive the address of the root
* directory.
* - Multiple directory entries can point to a directory. The entry in the
* parent directory points to a child directory. Any directories in the
* child directory contain a ".." entry that points back to the parent.
* The child directory itself contains a "." entry that points to itself.
* - The root directory does not contain a "." or ".." entry.
* - Directory entries for directories are never changed once they are created
* (except when removed). The size stays 0, and the last modification time
* is never changed. This is because so many directory entries can point to
* the physical clusters that make up a directory. It would lead to an
* update nightmare.
* - The length field in a directory entry pointing to a directory contains 0
* (always). The only way to find the end of a directory is to follow the
* cluster chain until the "last cluster" marker is found.
*
* My extensions to make this house of cards work. These apply only to the in
* memory copy of the directory entry.
* - A reference count for each denode will be kept since dos doesn't keep such
* things.
*/
/*
* Internal pseudo-offset for (nonexistent) directory entry for the root
* dir in the root dir
*/
#define MSDOSFSROOT_OFS 0x1fffffff
/*
* The fat cache structure. fc_fsrcn is the filesystem relative cluster
* number that corresponds to the file relative cluster number in this
* structure (fc_frcn).
*/
struct fatcache {
u_short fc_frcn; /* file relative cluster number */
u_short fc_fsrcn; /* filesystem relative cluster number */
};
/*
* The fat entry cache as it stands helps make extending files a "quick"
* operation by avoiding having to scan the fat to discover the last
* cluster of the file. The cache also helps sequential reads by
* remembering the last cluster read from the file. This also prevents us
* from having to rescan the fat to find the next cluster to read. This
* cache is probably pretty worthless if a file is opened by multiple
* processes.
*/
#define FC_SIZE 2 /* number of entries in the cache */
#define FC_LASTMAP 0 /* entry the last call to pcbmap() resolved
* to */
#define FC_LASTFC 1 /* entry for the last cluster in the file */
#define FCE_EMPTY 0xffff /* doesn't represent an actual cluster # */
/*
* Set a slot in the fat cache.
*/
#define fc_setcache(dep, slot, frcn, fsrcn) \
(dep)->de_fc[slot].fc_frcn = frcn; \
(dep)->de_fc[slot].fc_fsrcn = fsrcn;
/*
* This is the in memory variant of a dos directory entry. It is usually
* contained within a vnode.
*/
struct denode {
struct denode *de_next; /* Hash chain forward */
struct denode **de_prev; /* Hash chain back */
struct vnode *de_vnode; /* addr of vnode we are part of */
struct vnode *de_devvp; /* vnode of blk dev we live on */
u_long de_flag; /* flag bits */
dev_t de_dev; /* device where direntry lives */
u_long de_dirclust; /* cluster of the directory file containing this entry */
u_long de_diroffset; /* ordinal of this entry in the directory */
u_long de_fndclust; /* cluster of found dir entry */
u_long de_fndoffset; /* offset of found dir entry */
long de_refcnt; /* reference count */
struct msdosfsmount *de_pmp; /* addr of our mount struct */
struct lockf *de_lockf; /* byte level lock list */
struct lock de_lock; /* denode lock */
/* the next two fields must be contiguous in memory... */
u_char de_Name[8]; /* name, from directory entry */
u_char de_Extension[3]; /* extension, from directory entry */
u_char de_Attributes; /* attributes, from directory entry */
u_short de_Time; /* creation time */
u_short de_Date; /* creation date */
u_short de_StartCluster; /* starting cluster of file */
u_long de_FileSize; /* size of file in bytes */
struct fatcache de_fc[FC_SIZE]; /* fat cache */
u_quad_t de_modrev; /* Revision level for lease. */
};
/*
* Values for the de_flag field of the denode.
*/
#define DE_UPDATE 0x0004 /* modification time update request */
#define DE_MODIFIED 0x0080 /* denode has been modified, but DE_UPDATE
* isn't set */
/*
* Transfer directory entries between internal and external form.
* dep is a struct denode * (internal form),
* dp is a struct direntry * (external form).
*/
#define DE_INTERNALIZE(dep, dp) \
(bcopy((dp)->deName, (dep)->de_Name, 11), \
(dep)->de_Attributes = (dp)->deAttributes, \
(dep)->de_Time = getushort((dp)->deTime), \
(dep)->de_Date = getushort((dp)->deDate), \
(dep)->de_StartCluster = getushort((dp)->deStartCluster), \
(dep)->de_FileSize = getulong((dp)->deFileSize))
#define DE_EXTERNALIZE(dp, dep) \
(bcopy((dep)->de_Name, (dp)->deName, 11), \
bzero((dp)->deReserved, 10), \
(dp)->deAttributes = (dep)->de_Attributes, \
putushort((dp)->deTime, (dep)->de_Time), \
putushort((dp)->deDate, (dep)->de_Date), \
putushort((dp)->deStartCluster, (dep)->de_StartCluster), \
putulong((dp)->deFileSize, (dep)->de_FileSize))
#define de_forw de_chain[0]
#define de_back de_chain[1]
#ifdef KERNEL
#define VTODE(vp) ((struct denode *)(vp)->v_data)
#define DETOV(de) ((de)->de_vnode)
#define DE_TIMES(dep, t) \
if ((dep)->de_flag & DE_UPDATE) { \
if (!((dep)->de_Attributes & ATTR_DIRECTORY)) { \
struct timespec DE_TIMES_ts; \
(dep)->de_flag |= DE_MODIFIED; \
TIMEVAL_TO_TIMESPEC((t), &DE_TIMES_ts); \
unix2dostime(&DE_TIMES_ts, &(dep)->de_Date, \
&(dep)->de_Time); \
(dep)->de_Attributes |= ATTR_ARCHIVE; \
} \
(dep)->de_flag &= ~DE_UPDATE; \
}
/*
* This overlays the fid structure (see mount.h)
*/
struct defid {
u_short defid_len; /* length of structure */
u_short defid_pad; /* force long alignment */
u_long defid_dirclust; /* cluster this dir entry came from */
u_long defid_dirofs; /* index of entry within the cluster */
/* u_long defid_gen; generation number */
};
extern vop_t **msdosfs_vnodeop_p;
int msdosfs_lookup __P((struct vop_lookup_args *));
int msdosfs_inactive __P((struct vop_inactive_args *));
int msdosfs_reclaim __P((struct vop_reclaim_args *));
/*
* Internal service routine prototypes.
*/
int deget __P((struct msdosfsmount * pmp, u_long dirclust, u_long diroffset, struct direntry * direntptr, struct denode ** depp));
#endif /* KERNEL */
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