LCOM1920-T02G10

/*        $NetBSD: denode.h,v 1.24 2014/07/08 09:21:52 hannken Exp $        */

/*-

 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.

 * Copyright (C) 1994, 1995, 1997 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

 */

#ifndef _MSDOSFS_DENODE_H_

#define _MSDOSFS_DENODE_H_

#ifndef MAKEFS

#include <miscfs/genfs/genfs_node.h>

#else

struct genfs_node {

};

struct vnode;

struct msdosfsmount;

struct buf;

#endif

/*

 * 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_long fc_frcn;                /* file relative cluster number */

        u_long 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                3        /* 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        FC_NEXTTOLASTFC        2        /* entry for a close to the last cluster in the file */

#define        FCE_EMPTY        0xffffffff        /* 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;

#define fc_last_to_nexttolast(dep) \

        do {  \

                (dep)->de_fc[FC_NEXTTOLASTFC].fc_frcn = (dep)->de_fc[FC_LASTFC].fc_frcn; \

                (dep)->de_fc[FC_NEXTTOLASTFC].fc_fsrcn = (dep)->de_fc[FC_LASTFC].fc_fsrcn; \

        } while (0)

/*

 * This is the in memory variant of a dos directory entry.  It is usually

 * contained within a vnode.

 */

struct denode_key {

        u_long dk_dirclust;        /* cluster of the directory file containing this entry */

        u_long dk_diroffset;        /* offset of this entry in the directory cluster */

        void *dk_dirgen;        /* non zero and unique for unlinked nodes */

};

struct denode {

        struct genfs_node de_gnode;

        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 */

        struct denode_key de_key;

#define de_dirclust de_key.dk_dirclust

#define de_diroffset de_key.dk_diroffset

#define de_dirgen de_key.dk_dirgen

        u_long de_fndoffset;        /* offset of found dir entry */

        int de_fndcnt;                /* number of slots before de_fndoffset */

        long de_refcnt;                /* reference count */

        struct msdosfsmount *de_pmp;        /* addr of our mount struct */

        struct lockf *de_lockf;        /* byte level lock list */

        u_char de_Name[12];        /* name, from DOS directory entry */

        u_char de_Attributes;        /* attributes, from directory entry */

        u_char de_CHun;                /* Hundredth of second of CTime*/

        u_short de_CTime;        /* creation time */

        u_short de_CDate;        /* creation date */

        u_short de_ADate;        /* access date */

        u_short de_MTime;        /* modification time */

        u_short de_MDate;        /* modification date */

        u_long de_StartCluster; /* starting cluster of file */

        u_long de_FileSize;        /* size of file in bytes */

        struct fatcache de_fc[FC_SIZE];        /* FAT cache */

};

/*

 * Values for the de_flag field of the denode.

 */

#define        DE_UPDATE        0x0001        /* Modification time update request. */

#define        DE_CREATE        0x0002        /* Creation time update */

#define        DE_ACCESS        0x0004        /* Access time update */

#define        DE_MODIFIED        0x0008        /* Denode has been modified. */

#define        DE_RENAME        0x0010        /* Denode is in the process of being renamed */

/*

 * Maximum filename length in Win95

 * Note: Must be < sizeof(dirent.d_name)

 */

#define        WIN_MAXLEN        255

/* Maximum size of a file on a FAT filesystem */

#define MSDOSFS_FILESIZE_MAX        0xFFFFFFFFLL

/*

 * Transfer directory entries between internal and external form.

 * dep is a struct denode * (internal form),

 * dp is a struct direntry * (external form).

 */

#define DE_INTERNALIZE32(dep, dp)                        \

         ((dep)->de_StartCluster |= getushort((dp)->deHighClust) << 16)

#define DE_INTERNALIZE(dep, dp)                                \

        (memcpy((dep)->de_Name, (dp)->deName, 11),        \

         (dep)->de_Attributes = (dp)->deAttributes,        \

         (dep)->de_CHun = (dp)->deCHundredth,                \

         (dep)->de_CTime = getushort((dp)->deCTime),        \

         (dep)->de_CDate = getushort((dp)->deCDate),        \

         (dep)->de_ADate = getushort((dp)->deADate),        \

         (dep)->de_MTime = getushort((dp)->deMTime),        \

         (dep)->de_MDate = getushort((dp)->deMDate),        \

         (dep)->de_StartCluster = getushort((dp)->deStartCluster), \

         (dep)->de_FileSize = getulong((dp)->deFileSize), \

         (FAT32((dep)->de_pmp) ? DE_INTERNALIZE32((dep), (dp)) : 0))

#define DE_EXTERNALIZE32(dp, dep)                        \

         putushort((dp)->deHighClust, (dep)->de_StartCluster >> 16)

#define DE_EXTERNALIZE16(dp, dep)                        \

         putushort((dp)->deHighClust, 0)

#define DE_EXTERNALIZE(dp, dep)                                \

        (memcpy((dp)->deName, (dep)->de_Name, 11),        \

         (dp)->deAttributes = (dep)->de_Attributes,        \

         (dp)->deCHundredth = (dep)->de_CHun,                \

         putushort((dp)->deCTime, (dep)->de_CTime),        \

         putushort((dp)->deCDate, (dep)->de_CDate),        \

         putushort((dp)->deADate, (dep)->de_ADate),        \

         putushort((dp)->deMTime, (dep)->de_MTime),        \

         putushort((dp)->deMDate, (dep)->de_MDate),        \

         putushort((dp)->deStartCluster, (dep)->de_StartCluster), \

         putulong((dp)->deFileSize,                        \

             ((dep)->de_Attributes & ATTR_DIRECTORY) ? 0 : (dep)->de_FileSize), \

         (FAT32((dep)->de_pmp) ? DE_EXTERNALIZE32((dp), (dep)) : DE_EXTERNALIZE16((dp), (dep))))

#define        de_forw                de_chain[0]

#define        de_back                de_chain[1]

#if defined(_KERNEL) || defined(MAKEFS)

#define        VTODE(vp)        ((struct denode *)(vp)->v_data)

#define        DETOV(de)        ((de)->de_vnode)

#define        DETIMES(dep, acc, mod, cre, gmtoff) \

        while ((dep)->de_flag & (DE_UPDATE | DE_CREATE | DE_ACCESS)) \

                msdosfs_detimes(dep, acc, mod, cre, gmtoff)

/*

 * This overlays the fid structure (see fstypes.h)

 */

struct defid {

        u_int16_t defid_len;        /* length of structure */

        u_int16_t defid_pad;        /* force 4-byte alignment */

        u_int32_t defid_dirclust; /* cluster this dir entry came from */

        u_int32_t defid_dirofs;        /* offset of entry within the cluster */

        u_int32_t defid_gen;        /* generation number */

};

/*

 * Prototypes for MSDOSFS vnode operations

 */

int        msdosfs_lookup                (void *);

int        msdosfs_create                (void *);

int        msdosfs_close                (void *);

int        msdosfs_access                (void *);

int        msdosfs_getattr                (void *);

int        msdosfs_setattr                (void *);

int        msdosfs_read                (void *);

int        msdosfs_write                (void *);

#define        msdosfs_lease_check        genfs_lease_check

#define        msdosfs_ioctl                genfs_enoioctl

#define        msdosfs_poll                genfs_poll

#define        msdosfs_revoke                genfs_revoke

#define        msdosfs_mmap                genfs_mmap

int        msdosfs_fsync                (void *);

#define        msdosfs_seek                genfs_seek

int        msdosfs_remove                (void *);

int        msdosfs_rename                (void *);

int        msdosfs_mkdir                (void *);

int        msdosfs_rmdir                (void *);

int        msdosfs_readdir                (void *);

#define        msdosfs_abortop                genfs_abortop

int        msdosfs_inactive        (void *);

int        msdosfs_reclaim                (void *);

int        msdosfs_bmap                (void *);

int        msdosfs_strategy        (void *);

int        msdosfs_print                (void *);

int        msdosfs_advlock                (void *);

int        msdosfs_pathconf        (void *);

/*

 * Internal service routine prototypes.

 */

struct componentname;

struct direntry;

struct kauth_cred;

int msdosfs_update(struct vnode *, const struct timespec *,

            const struct timespec *, int);

int createde(struct denode *, struct denode *,

                struct denode **, struct componentname *);

int deextend(struct denode *, u_long, struct kauth_cred *);

#ifdef MAKEFS

int deget(struct msdosfsmount *, u_long, u_long, struct denode **);

#else

int deget(struct msdosfsmount *, u_long, u_long, struct vnode **);

#endif

int detrunc(struct denode *, u_long, int, struct kauth_cred *);

int deupdat(struct denode *, int);

int doscheckpath(struct denode *, struct denode *);

int dosdirempty(struct denode *);

int readde(struct denode *, struct buf **, struct direntry **);

int readep(struct msdosfsmount *, u_long, u_long,

                struct buf **, struct direntry **);

int removede(struct denode *, struct denode *);

int uniqdosname(struct denode *, struct componentname *, u_char *);

int findwin95(struct denode *);

int msdosfs_gop_alloc(struct vnode *, off_t, off_t, int, struct kauth_cred *);

void msdosfs_gop_markupdate(struct vnode *, int);

void msdosfs_detimes(struct denode *, const struct timespec *,

    const struct timespec *, const struct timespec *, int);

int msdosfs_fh_enter(struct msdosfsmount *, uint32_t, uint32_t, uint32_t *);

int msdosfs_fh_remove(struct msdosfsmount *, uint32_t, uint32_t);

int msdosfs_fh_lookup(struct msdosfsmount *, uint32_t, uint32_t, uint32_t *);

void msdosfs_fh_destroy(struct msdosfsmount *);

#endif        /* _KERNEL || MAKEFS */

#endif /* _MSDOSFS_DENODE_H_ */