freebsd-skq/sys/fs/ntfs/ntfs_ihash.c

130 lines
3.7 KiB
C

/* $NetBSD: ntfs_ihash.c,v 1.5 1999/09/30 16:56:40 jdolecek Exp $ */
/*-
* 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.
* 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
* $FreeBSD$
*/
#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/mount.h>
#include <sys/mutex.h>
#include <fs/ntfs/ntfs.h>
#include <fs/ntfs/ntfs_inode.h>
#include <fs/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[(minor(device) + (inum)) & ntfs_nthash])
static struct mtx ntfs_nthash_mtx;
struct lock ntfs_hashlock;
/*
* Initialize inode hash table.
*/
void
ntfs_nthashinit()
{
lockinit(&ntfs_hashlock, PINOD, "ntfs_nthashlock", 0, 0);
ntfs_nthashtbl = hashinit(desiredvnodes, M_NTFSNTHASH, &ntfs_nthash);
mtx_init(&ntfs_nthash_mtx, "ntfs nthash", NULL, MTX_DEF);
}
/*
* Destroy inode hash table.
*/
void
ntfs_nthashdestroy(void)
{
lockdestroy(&ntfs_hashlock);
mtx_destroy(&ntfs_nthash_mtx);
}
/*
* 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)
struct cdev *dev;
ino_t inum;
{
struct ntnode *ip;
mtx_lock(&ntfs_nthash_mtx);
LIST_FOREACH(ip, NTNOHASH(dev, inum), i_hash)
if (inum == ip->i_number && dev == ip->i_dev)
break;
mtx_unlock(&ntfs_nthash_mtx);
return (ip);
}
/*
* Insert the ntnode into the hash table.
*/
void
ntfs_nthashins(ip)
struct ntnode *ip;
{
struct nthashhead *ipp;
mtx_lock(&ntfs_nthash_mtx);
ipp = NTNOHASH(ip->i_dev, ip->i_number);
LIST_INSERT_HEAD(ipp, ip, i_hash);
ip->i_flag |= IN_HASHED;
mtx_unlock(&ntfs_nthash_mtx);
}
/*
* Remove the inode from the hash table.
*/
void
ntfs_nthashrem(ip)
struct ntnode *ip;
{
mtx_lock(&ntfs_nthash_mtx);
if (ip->i_flag & IN_HASHED) {
ip->i_flag &= ~IN_HASHED;
LIST_REMOVE(ip, i_hash);
}
mtx_unlock(&ntfs_nthash_mtx);
}