diff options
Diffstat (limited to 'sys/pcfs/denode.h')
| -rw-r--r-- | sys/pcfs/denode.h | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/sys/pcfs/denode.h b/sys/pcfs/denode.h new file mode 100644 index 000000000000..ddd964ecbeee --- /dev/null +++ b/sys/pcfs/denode.h @@ -0,0 +1,248 @@ +/* + * 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 + * + * $Id: denode.h,v 1.2 1993/10/16 19:29:26 rgrimes Exp $ + */ + +/* + * This is the pc filesystem specific portion of the + * vnode structure. + * To describe a file uniquely the de_dirclust, de_diroffset, + * and de_de.deStartCluster 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_de.deStartCluster 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 child. 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 PCFSROOT_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_chain[2]; /* hash chain ptrs */ + 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 */ + long de_refcnt; /* reference count */ + struct pcfsmount *de_pmp; /* addr of our mount struct */ + struct lockf *de_lockf; /* byte level lock list */ + long de_spare0; /* current lock holder */ + long de_spare1; /* lock wanter */ + struct direntry de_de; /* the actual directory entry */ + struct fatcache de_fc[FC_SIZE]; /* fat cache */ +}; + +/* + * Values for the de_flag field of the denode. + */ +#define DELOCKED 0x0001 /* directory entry is locked */ +#define DEWANT 0x0002 /* someone wants this de */ +#define DERENAME 0x0004 /* de is being renamed */ +#define DEUPD 0x0008 /* file has been modified */ +#define DESHLOCK 0x0010 /* file has shared lock */ +#define DEEXLOCK 0x0020 /* file has exclusive lock */ +#define DELWAIT 0x0040 /* someone waiting on file lock */ +#define DEMOD 0x0080 /* denode wants to be written back + * to disk */ + +/* + * Shorthand macros used to reference fields in the direntry + * contained in the denode structure. + */ +#define de_Name de_de.deName +#define de_Extension de_de.deExtension +#define de_Attributes de_de.deAttributes +#define de_Reserved de_de.deReserved +#define de_Time de_de.deTime +#define de_Date de_de.deDate +#define de_StartCluster de_de.deStartCluster +#define de_FileSize de_de.deFileSize +#define de_forw de_chain[0] +#define de_back de_chain[1] + +#if defined(KERNEL) + +#define VTODE(vp) ((struct denode *)(vp)->v_data) +#define DETOV(de) ((de)->de_vnode) + +#define DELOCK(de) delock(de) +#define DEUNLOCK(de) deunlock(de) + +#define DEUPDAT(dep, t, waitfor) \ + if (dep->de_flag & DEUPD) \ + (void) deupdat(dep, t, waitfor); + +#define DETIMES(dep, t) \ + if (dep->de_flag & DEUPD) { \ + (dep)->de_flag |= DEMOD; \ + unix2dostime(t, (union dosdate *)&dep->de_Date, \ + (union dostime *)&dep->de_Time); \ + (dep)->de_flag &= ~DEUPD; \ + } + +/* + * This overlays the fid sturcture (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 */ +}; + +/* + * Prototypes for PCFS vnode operations + */ +int pcfs_lookup __P((struct vnode *vp, struct nameidata *ndp, struct proc *p)); +int pcfs_create __P((struct nameidata *ndp, struct vattr *vap, struct proc *p)); +int pcfs_mknod __P((struct nameidata *ndp, struct vattr *vap, struct ucred *cred, + struct proc *p)); +int pcfs_open __P((struct vnode *vp, int mode, struct ucred *cred, + struct proc *p)); +int pcfs_close __P((struct vnode *vp, int fflag, struct ucred *cred, + struct proc *p)); +int pcfs_access __P((struct vnode *vp, int mode, struct ucred *cred, + struct proc *p)); +int pcfs_getattr __P((struct vnode *vp, struct vattr *vap, struct ucred *cred, + struct proc *p)); +int pcfs_setattr __P((struct vnode *vp, struct vattr *vap, struct ucred *cred, + struct proc *p)); +int pcfs_read __P((struct vnode *vp, struct uio *uio, int ioflag, + struct ucred *cred)); +int pcfs_write __P((struct vnode *vp, struct uio *uio, int ioflag, + struct ucred *cred)); +int pcfs_ioctl __P((struct vnode *vp, int command, caddr_t data, int fflag, + struct ucred *cred, struct proc *p)); +int pcfs_select __P((struct vnode *vp, int which, int fflags, struct ucred *cred, + struct proc *p)); +int pcfs_mmap __P((struct vnode *vp, int fflags, struct ucred *cred, + struct proc *p)); +int pcfs_fsync __P((struct vnode *vp, int fflags, struct ucred *cred, + int waitfor, struct proc *p)); +int pcfs_seek __P((struct vnode *vp, off_t oldoff, off_t newoff, + struct ucred *cred)); +int pcfs_remove __P((struct nameidata *ndp, struct proc *p)); +int pcfs_link __P((struct vnode *vp, struct nameidata *ndp, struct proc *p)); +int pcfs_rename __P((struct nameidata *fndp, struct nameidata *tdnp, + struct proc *p)); +int pcfs_mkdir __P((struct nameidata *ndp, struct vattr *vap, struct proc *p)); +int pcfs_rmdir __P((struct nameidata *ndp, struct proc *p)); +int pcfs_symlink __P((struct nameidata *ndp, struct vattr *vap, char *target, + struct proc *p)); +int pcfs_readdir __P((struct vnode *vp, struct uio *uio, struct ucred *cred, + int *eofflagp)); +int pcfs_readlink __P((struct vnode *vp, struct uio *uio, struct ucred *cred)); +int pcfs_abortop __P((struct nameidata *ndp)); +int pcfs_inactive __P((struct vnode *vp, struct proc *p)); +int pcfs_reclaim __P((struct vnode *vp)); +int pcfs_lock __P((struct vnode *vp)); +int pcfs_unlock __P((struct vnode *vp)); +int pcfs_bmap __P((struct vnode *vp, daddr_t bn, struct vnode **vpp, + daddr_t *bnp)); +int pcfs_strategy __P((struct buf *bp)); +int pcfs_print __P((struct vnode *vp)); +int pcfs_islocked __P((struct vnode *vp)); +int pcfs_advlock __P((struct vnode *vp, caddr_t id, int op, struct flock *fl, + int flags)); + +/* + * Internal service routine prototypes. + */ +int deget __P((struct pcfsmount *pmp, u_long dirclust, u_long diroffset, + struct direntry *direntptr, struct denode **depp)); +#endif /* defined(KERNEL) */ |