freebsd-skq/sys/ntfs/ntfs_ihash.c
semenu 05d36e7aea Added limited write ability. Now we can use some kind
of files for swap holders. See mount_ntfs..8 for details.
1999-02-19 12:31:02 +00:00

126 lines
3.8 KiB
C

/*
* Copyright (c) 1982, 1986, 1989, 1991, 1993, 1995
* The 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.
*
* @(#)ufs_ihash.c 8.7 (Berkeley) 5/17/95
* $Id: ntfs_ihash.c,v 1.2 1999/01/02 01:17:38 semen Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <ntfs/ntfs.h>
#include <ntfs/ntfs_inode.h>
#include <ntfs/ntfs_ihash.h>
MALLOC_DEFINE(M_NTFSNTHASH, "NTFS nthash", "NTFS ntnode hash tables");
/*
* Structures associated with inode cacheing.
*/
static LIST_HEAD(nthashhead, ntnode) *ntfs_nthashtbl;
static u_long ntfs_nthash; /* size of hash table - 1 */
#define NTNOHASH(device, inum) (&ntfs_nthashtbl[((device) + (inum)) & ntfs_nthash])
#ifndef NULL_SIMPLELOCKS
static struct simplelock ntfs_nthash_slock;
#endif
/*
* Initialize inode hash table.
*/
void
ntfs_nthashinit()
{
ntfs_nthashtbl = hashinit(desiredvnodes, M_NTFSNTHASH, &ntfs_nthash);
simple_lock_init(&ntfs_nthash_slock);
}
/*
* Use the device/inum pair to find the incore inode, and return a pointer
* to it. If it is in core, return it, even if it is locked.
*/
struct ntnode *
ntfs_nthashlookup(dev, inum)
dev_t dev;
ino_t inum;
{
struct ntnode *ip;
simple_lock(&ntfs_nthash_slock);
for (ip = NTNOHASH(dev, inum)->lh_first; ip; ip = ip->i_hash.le_next)
if (inum == ip->i_number && dev == ip->i_dev)
break;
simple_unlock(&ntfs_nthash_slock);
return (ip);
}
/*
* Insert the ntnode into the hash table.
*/
void
ntfs_nthashins(ip)
struct ntnode *ip;
{
struct nthashhead *ipp;
simple_lock(&ntfs_nthash_slock);
ipp = NTNOHASH(ip->i_dev, ip->i_number);
LIST_INSERT_HEAD(ipp, ip, i_hash);
ip->i_flag |= IN_HASHED;
simple_unlock(&ntfs_nthash_slock);
}
/*
* Remove the inode from the hash table.
*/
void
ntfs_nthashrem(ip)
struct ntnode *ip;
{
simple_lock(&ntfs_nthash_slock);
if (ip->i_flag & IN_HASHED) {
ip->i_flag &= ~IN_HASHED;
LIST_REMOVE(ip, i_hash);
#ifdef DIAGNOSTIC
ip->i_hash.le_next = NULL;
ip->i_hash.le_prev = NULL;
#endif
}
simple_unlock(&ntfs_nthash_slock);
}