ntfs_ihash.c revision 66615
1/* $NetBSD: ntfs_ihash.c,v 1.5 1999/09/30 16:56:40 jdolecek Exp $ */ 2 3/* 4 * Copyright (c) 1982, 1986, 1989, 1991, 1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)ufs_ihash.c 8.7 (Berkeley) 5/17/95 36 * $FreeBSD: head/sys/fs/ntfs/ntfs_ihash.c 66615 2000-10-04 01:29:17Z jasone $ 37 */ 38 39#include <sys/param.h> 40#include <sys/systm.h> 41#include <sys/kernel.h> 42#include <sys/lock.h> 43#include <sys/vnode.h> 44#include <sys/malloc.h> 45#include <sys/proc.h> 46#include <sys/mount.h> 47 48#include <ntfs/ntfs.h> 49#include <ntfs/ntfs_inode.h> 50#include <ntfs/ntfs_ihash.h> 51 52MALLOC_DEFINE(M_NTFSNTHASH, "NTFS nthash", "NTFS ntnode hash tables"); 53 54/* 55 * Structures associated with inode cacheing. 56 */ 57static LIST_HEAD(nthashhead, ntnode) *ntfs_nthashtbl; 58static u_long ntfs_nthash; /* size of hash table - 1 */ 59#define NTNOHASH(device, inum) (&ntfs_nthashtbl[(minor(device) + (inum)) & ntfs_nthash]) 60#ifndef NULL_SIMPLELOCKS 61static struct simplelock ntfs_nthash_slock; 62#endif 63struct lock ntfs_hashlock; 64 65/* 66 * Initialize inode hash table. 67 */ 68void 69ntfs_nthashinit() 70{ 71 lockinit(&ntfs_hashlock, PINOD, "ntfs_nthashlock", 0, 0); 72 ntfs_nthashtbl = HASHINIT(desiredvnodes, M_NTFSNTHASH, M_WAITOK, 73 &ntfs_nthash); 74 simple_lock_init(&ntfs_nthash_slock); 75} 76 77/* 78 * Destroy inode hash table. 79 */ 80void 81ntfs_nthashdestroy(void) 82{ 83 lockdestroy(&ntfs_hashlock); 84} 85 86/* 87 * Use the device/inum pair to find the incore inode, and return a pointer 88 * to it. If it is in core, return it, even if it is locked. 89 */ 90struct ntnode * 91ntfs_nthashlookup(dev, inum) 92 dev_t dev; 93 ino_t inum; 94{ 95 struct ntnode *ip; 96 97 simple_lock(&ntfs_nthash_slock); 98 for (ip = NTNOHASH(dev, inum)->lh_first; ip; ip = ip->i_hash.le_next) 99 if (inum == ip->i_number && dev == ip->i_dev) 100 break; 101 simple_unlock(&ntfs_nthash_slock); 102 103 return (ip); 104} 105 106/* 107 * Insert the ntnode into the hash table. 108 */ 109void 110ntfs_nthashins(ip) 111 struct ntnode *ip; 112{ 113 struct nthashhead *ipp; 114 115 simple_lock(&ntfs_nthash_slock); 116 ipp = NTNOHASH(ip->i_dev, ip->i_number); 117 LIST_INSERT_HEAD(ipp, ip, i_hash); 118 ip->i_flag |= IN_HASHED; 119 simple_unlock(&ntfs_nthash_slock); 120} 121 122/* 123 * Remove the inode from the hash table. 124 */ 125void 126ntfs_nthashrem(ip) 127 struct ntnode *ip; 128{ 129 simple_lock(&ntfs_nthash_slock); 130 if (ip->i_flag & IN_HASHED) { 131 ip->i_flag &= ~IN_HASHED; 132 LIST_REMOVE(ip, i_hash); 133#ifdef DIAGNOSTIC 134 ip->i_hash.le_next = NULL; 135 ip->i_hash.le_prev = NULL; 136#endif 137 } 138 simple_unlock(&ntfs_nthash_slock); 139} 140