NetBSD/sys/isofs/isofs_node.c

283 lines
7.1 KiB
C

/*
* Copyright (c) 1982, 1986, 1989 Regents of the University of California.
* All rights reserved.
*
* 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 the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS OR CONTRIBUTORS 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.
*
* @(#)isofs_inode.c
*/
#include "param.h"
#include "systm.h"
#include "mount.h"
#include "proc.h"
#include "file.h"
#include "buf.h"
#include "vnode.h"
#include "kernel.h"
#include "malloc.h"
#include "iso.h"
#include "isofs_node.h"
#define INOHSZ 512
#if ((INOHSZ&(INOHSZ-1)) == 0)
#define INOHASH(dev,ino) (((dev)+(ino))&(INOHSZ-1))
#else
#define INOHASH(dev,ino) (((unsigned)((dev)+(ino)))%INOHSZ)
#endif
union iso_ihead {
union iso_ihead *ih_head[2];
struct iso_node *ih_chain[2];
} iso_ihead[INOHSZ];
int prtactive; /* 1 => print out reclaim of active vnodes */
/*
* Initialize hash links for inodes.
*/
isofs_init()
{
register int i;
register union iso_ihead *ih = iso_ihead;
#ifndef lint
if (VN_MAXPRIVATE < sizeof(struct iso_node))
panic("ihinit: too small");
#endif /* not lint */
for (i = INOHSZ; --i >= 0; ih++) {
ih->ih_head[0] = ih;
ih->ih_head[1] = ih;
}
}
/*
* Look up a ISOFS dinode number to find its incore vnode.
* If it is not in core, read it in from the specified device.
* If it is in core, wait for the lock bit to clear, then
* return the inode locked. Detection and handling of mount
* points must be done by the calling routine.
*/
iso_iget(xp, ino, ipp, isodir)
struct iso_node *xp;
ino_t ino;
struct iso_node **ipp;
struct iso_directory_record *isodir;
{
dev_t dev = xp->i_dev;
struct mount *mntp = ITOV(xp)->v_mount;
extern struct vnodeops isofs_vnodeops, spec_inodeops;
register struct iso_node *ip, *iq;
register struct vnode *vp;
struct vnode *nvp;
struct buf *bp;
struct dinode *dp;
union iso_ihead *ih;
int i, error;
struct iso_mnt *imp;
ih = &iso_ihead[INOHASH(dev, ino)];
loop:
for (ip = ih->ih_chain[0];
ip != (struct iso_node *)ih;
ip = ip->i_forw) {
if (ino != ip->i_number || dev != ip->i_dev)
continue;
if ((ip->i_flag&ILOCKED) != 0) {
ip->i_flag |= IWANT;
sleep((caddr_t)ip, PINOD);
goto loop;
}
if (vget(ITOV(ip)))
goto loop;
*ipp = ip;
return(0);
}
/*
* Allocate a new inode.
*/
if (error = getnewvnode(VT_ISOFS, mntp, &isofs_vnodeops, &nvp)) {
*ipp = 0;
return (error);
}
ip = VTOI(nvp);
ip->i_vnode = nvp;
ip->i_flag = 0;
ip->i_devvp = 0;
ip->i_diroff = 0;
ip->i_lockf = 0;
/*
* Put it onto its hash chain and lock it so that other requests for
* this inode will block if they arrive while we are sleeping waiting
* for old data structures to be purged or for the contents of the
* disk portion of this inode to be read.
*/
ip->i_dev = dev;
ip->i_number = ino;
insque(ip, ih);
ISO_ILOCK(ip);
ip->iso_reclen = isonum_711 (isodir->length);
ip->iso_extlen = isonum_711 (isodir->ext_attr_length);
ip->iso_extent = isonum_733 (isodir->extent);
ip->i_size = isonum_733 (isodir->size);
bcopy (isodir->date, ip->iso_time, sizeof ip->iso_time);
ip->iso_flags = isonum_711 (isodir->flags);
ip->iso_unit_size = isonum_711 (isodir->file_unit_size);
ip->iso_interleave_gap = isonum_711 (isodir->interleave);
ip->iso_volume_seq = isonum_723 (isodir->volume_sequence_number);
ip->iso_namelen = isonum_711 (isodir->name_len);
/*
* Initialize the associated vnode
*/
vp = ITOV(ip);
if (ip->iso_flags & 2)
vp->v_type = VDIR;
else
vp->v_type = VREG;
imp = VFSTOISOFS (mntp);
if (ino == imp->root_extent)
vp->v_flag |= VROOT;
/*
* Finish inode initialization.
*/
ip->i_mnt = imp;
ip->i_devvp = imp->im_devvp;
VREF(ip->i_devvp);
*ipp = ip;
return (0);
}
/*
* Unlock and decrement the reference count of an inode structure.
*/
iso_iput(ip)
register struct iso_node *ip;
{
if ((ip->i_flag & ILOCKED) == 0)
panic("iso_iput");
ISO_IUNLOCK(ip);
vrele(ITOV(ip));
}
/*
* Last reference to an inode, write the inode out and if necessary,
* truncate and deallocate the file.
*/
isofs_inactive(vp, p)
struct vnode *vp;
struct proc *p;
{
register struct iso_node *ip = VTOI(vp);
int mode, error = 0;
if (prtactive && vp->v_usecount != 0)
vprint("isofs_inactive: pushing active", vp);
ip->i_flag = 0;
/*
* If we are done with the inode, reclaim it
* so that it can be reused immediately.
*/
if (vp->v_usecount == 0 /* && ip->i_mode == 0 */)
vgone(vp);
return (error);
}
/*
* Reclaim an inode so that it can be used for other purposes.
*/
isofs_reclaim(vp)
register struct vnode *vp;
{
register struct iso_node *ip = VTOI(vp);
int i;
if (prtactive && vp->v_usecount != 0)
vprint("isofs_reclaim: pushing active", vp);
/*
* Remove the inode from its hash chain.
*/
remque(ip);
ip->i_forw = ip;
ip->i_back = ip;
/*
* Purge old data structures associated with the inode.
*/
cache_purge(vp);
if (ip->i_devvp) {
vrele(ip->i_devvp);
ip->i_devvp = 0;
}
ip->i_flag = 0;
return (0);
}
/*
* Lock an inode. If its already locked, set the WANT bit and sleep.
*/
iso_ilock(ip)
register struct iso_node *ip;
{
while (ip->i_flag & ILOCKED) {
ip->i_flag |= IWANT;
if (ip->i_spare0 == curproc->p_pid)
panic("locking against myself");
ip->i_spare1 = curproc->p_pid;
(void) sleep((caddr_t)ip, PINOD);
}
ip->i_spare1 = 0;
ip->i_spare0 = curproc->p_pid;
ip->i_flag |= ILOCKED;
}
/*
* Unlock an inode. If WANT bit is on, wakeup.
*/
iso_iunlock(ip)
register struct iso_node *ip;
{
if ((ip->i_flag & ILOCKED) == 0)
vprint("iso_iunlock: unlocked inode", ITOV(ip));
ip->i_spare0 = 0;
ip->i_flag &= ~ILOCKED;
if (ip->i_flag&IWANT) {
ip->i_flag &= ~IWANT;
wakeup((caddr_t)ip);
}
}