1 /* $NetBSD: ntfs_ihash.c,v 1.7 2008/05/05 17:11:16 ad 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)ufs_ihash.c 8.7 (Berkeley) 5/17/95 32 * Id: ntfs_ihash.c,v 1.5 1999/05/12 09:42:58 semenu Exp 33 */ 34 35 #include <sys/cdefs.h> 36 __KERNEL_RCSID(0, "$NetBSD: ntfs_ihash.c,v 1.7 2008/05/05 17:11:16 ad Exp $"); 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/kernel.h> 41 #include <sys/lock.h> 42 #include <sys/vnode.h> 43 #include <sys/proc.h> 44 #include <sys/mount.h> 45 46 #include <fs/ntfs/ntfs.h> 47 #include <fs/ntfs/ntfs_inode.h> 48 #include <fs/ntfs/ntfs_ihash.h> 49 50 /* 51 * Structures associated with inode cacheing. 52 */ 53 static LIST_HEAD(nthashhead, ntnode) *ntfs_nthashtbl; 54 static u_long ntfs_nthash; /* size of hash table - 1 */ 55 #define NTNOHASH(device, inum) ((minor(device) + (inum)) & ntfs_nthash) 56 static kmutex_t ntfs_nthash_lock; 57 kmutex_t ntfs_hashlock; 58 59 /* 60 * Initialize inode hash table. 61 */ 62 void 63 ntfs_nthashinit() 64 { 65 mutex_init(&ntfs_hashlock, MUTEX_DEFAULT, IPL_NONE); 66 mutex_init(&ntfs_nthash_lock, MUTEX_DEFAULT, IPL_NONE); 67 ntfs_nthashtbl = hashinit(desiredvnodes, HASH_LIST, true, &ntfs_nthash); 68 } 69 70 /* 71 * Reinitialize inode hash table. 72 */ 73 74 void 75 ntfs_nthashreinit() 76 { 77 struct ntnode *ip; 78 struct nthashhead *oldhash, *hash; 79 u_long oldmask, mask, val; 80 int i; 81 82 hash = hashinit(desiredvnodes, HASH_LIST, true, &mask); 83 84 mutex_enter(&ntfs_nthash_lock); 85 oldhash = ntfs_nthashtbl; 86 oldmask = ntfs_nthash; 87 ntfs_nthashtbl = hash; 88 ntfs_nthash = mask; 89 for (i = 0; i <= oldmask; i++) { 90 while ((ip = LIST_FIRST(&oldhash[i])) != NULL) { 91 LIST_REMOVE(ip, i_hash); 92 val = NTNOHASH(ip->i_dev, ip->i_number); 93 LIST_INSERT_HEAD(&hash[val], ip, i_hash); 94 } 95 } 96 mutex_exit(&ntfs_nthash_lock); 97 hashdone(oldhash, HASH_LIST, oldmask); 98 } 99 100 /* 101 * Free the inode hash table. Called from ntfs_done(), only needed 102 * on NetBSD. 103 */ 104 void 105 ntfs_nthashdone() 106 { 107 hashdone(ntfs_nthashtbl, HASH_LIST, ntfs_nthash); 108 mutex_destroy(&ntfs_hashlock); 109 mutex_destroy(&ntfs_nthash_lock); 110 } 111 112 /* 113 * Use the device/inum pair to find the incore inode, and return a pointer 114 * to it. If it is in core, return it, even if it is locked. 115 */ 116 struct ntnode * 117 ntfs_nthashlookup(dev, inum) 118 dev_t dev; 119 ino_t inum; 120 { 121 struct ntnode *ip; 122 struct nthashhead *ipp; 123 124 mutex_enter(&ntfs_nthash_lock); 125 ipp = &ntfs_nthashtbl[NTNOHASH(dev, inum)]; 126 LIST_FOREACH(ip, ipp, i_hash) { 127 if (inum == ip->i_number && dev == ip->i_dev) 128 break; 129 } 130 mutex_exit(&ntfs_nthash_lock); 131 132 return (ip); 133 } 134 135 /* 136 * Insert the ntnode into the hash table. 137 */ 138 void 139 ntfs_nthashins(ip) 140 struct ntnode *ip; 141 { 142 struct nthashhead *ipp; 143 144 mutex_enter(&ntfs_nthash_lock); 145 ipp = &ntfs_nthashtbl[NTNOHASH(ip->i_dev, ip->i_number)]; 146 LIST_INSERT_HEAD(ipp, ip, i_hash); 147 ip->i_flag |= IN_HASHED; 148 mutex_exit(&ntfs_nthash_lock); 149 } 150 151 /* 152 * Remove the inode from the hash table. 153 */ 154 void 155 ntfs_nthashrem(ip) 156 struct ntnode *ip; 157 { 158 mutex_enter(&ntfs_nthash_lock); 159 if (ip->i_flag & IN_HASHED) { 160 ip->i_flag &= ~IN_HASHED; 161 LIST_REMOVE(ip, i_hash); 162 } 163 mutex_exit(&ntfs_nthash_lock); 164 } 165