1 /* $NetBSD: ntfs_ihash.c,v 1.6 2007/06/30 09:37:56 pooka 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 1.6 2007/06/30 09:37:56 pooka 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/malloc.h> 44 #include <sys/proc.h> 45 #include <sys/mount.h> 46 47 #include <fs/ntfs/ntfs.h> 48 #include <fs/ntfs/ntfs_inode.h> 49 #include <fs/ntfs/ntfs_ihash.h> 50 51 MALLOC_JUSTDEFINE(M_NTFSNTHASH, "NTFS nthash", "NTFS ntnode hash tables"); 52 53 /* 54 * Structures associated with inode cacheing. 55 */ 56 static LIST_HEAD(nthashhead, ntnode) *ntfs_nthashtbl; 57 static u_long ntfs_nthash; /* size of hash table - 1 */ 58 #define NTNOHASH(device, inum) ((minor(device) + (inum)) & ntfs_nthash) 59 static kmutex_t ntfs_nthash_lock; 60 kmutex_t ntfs_hashlock; 61 62 /* 63 * Initialize inode hash table. 64 */ 65 void 66 ntfs_nthashinit() 67 { 68 mutex_init(&ntfs_hashlock, MUTEX_DEFAULT, IPL_NONE); 69 mutex_init(&ntfs_nthash_lock, MUTEX_DEFAULT, IPL_NONE); 70 ntfs_nthashtbl = HASHINIT(desiredvnodes, M_NTFSNTHASH, M_WAITOK, 71 &ntfs_nthash); 72 } 73 74 /* 75 * Reinitialize inode hash table. 76 */ 77 78 void 79 ntfs_nthashreinit() 80 { 81 struct ntnode *ip; 82 struct nthashhead *oldhash, *hash; 83 u_long oldmask, mask, val; 84 int i; 85 86 hash = HASHINIT(desiredvnodes, M_NTFSNTHASH, M_WAITOK, &mask); 87 88 mutex_enter(&ntfs_nthash_lock); 89 oldhash = ntfs_nthashtbl; 90 oldmask = ntfs_nthash; 91 ntfs_nthashtbl = hash; 92 ntfs_nthash = mask; 93 for (i = 0; i <= oldmask; i++) { 94 while ((ip = LIST_FIRST(&oldhash[i])) != NULL) { 95 LIST_REMOVE(ip, i_hash); 96 val = NTNOHASH(ip->i_dev, ip->i_number); 97 LIST_INSERT_HEAD(&hash[val], ip, i_hash); 98 } 99 } 100 mutex_exit(&ntfs_nthash_lock); 101 hashdone(oldhash, M_NTFSNTHASH); 102 } 103 104 /* 105 * Free the inode hash table. Called from ntfs_done(), only needed 106 * on NetBSD. 107 */ 108 void 109 ntfs_nthashdone() 110 { 111 hashdone(ntfs_nthashtbl, M_NTFSNTHASH); 112 mutex_destroy(&ntfs_hashlock); 113 mutex_destroy(&ntfs_nthash_lock); 114 } 115 116 /* 117 * Use the device/inum pair to find the incore inode, and return a pointer 118 * to it. If it is in core, return it, even if it is locked. 119 */ 120 struct ntnode * 121 ntfs_nthashlookup(dev, inum) 122 dev_t dev; 123 ino_t inum; 124 { 125 struct ntnode *ip; 126 struct nthashhead *ipp; 127 128 mutex_enter(&ntfs_nthash_lock); 129 ipp = &ntfs_nthashtbl[NTNOHASH(dev, inum)]; 130 LIST_FOREACH(ip, ipp, i_hash) { 131 if (inum == ip->i_number && dev == ip->i_dev) 132 break; 133 } 134 mutex_exit(&ntfs_nthash_lock); 135 136 return (ip); 137 } 138 139 /* 140 * Insert the ntnode into the hash table. 141 */ 142 void 143 ntfs_nthashins(ip) 144 struct ntnode *ip; 145 { 146 struct nthashhead *ipp; 147 148 mutex_enter(&ntfs_nthash_lock); 149 ipp = &ntfs_nthashtbl[NTNOHASH(ip->i_dev, ip->i_number)]; 150 LIST_INSERT_HEAD(ipp, ip, i_hash); 151 ip->i_flag |= IN_HASHED; 152 mutex_exit(&ntfs_nthash_lock); 153 } 154 155 /* 156 * Remove the inode from the hash table. 157 */ 158 void 159 ntfs_nthashrem(ip) 160 struct ntnode *ip; 161 { 162 mutex_enter(&ntfs_nthash_lock); 163 if (ip->i_flag & IN_HASHED) { 164 ip->i_flag &= ~IN_HASHED; 165 LIST_REMOVE(ip, i_hash); 166 } 167 mutex_exit(&ntfs_nthash_lock); 168 } 169