1 /* 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993, 1995 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)ufs_ihash.c 8.7 (Berkeley) 5/17/95 34 * $FreeBSD: src/sys/fs/hpfs/hpfs_hash.c,v 1.1 1999/12/09 19:09:58 semenu Exp $ 35 * $DragonFly: src/sys/vfs/hpfs/hpfs_hash.c,v 1.5 2003/07/19 21:14:31 dillon Exp $ 36 */ 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/mount.h> 44 #include <sys/malloc.h> 45 #include <sys/proc.h> 46 47 #include <fs/hpfs/hpfs.h> 48 49 MALLOC_DEFINE(M_HPFSHASH, "HPFS hash", "HPFS node hash tables"); 50 51 /* 52 * Structures associated with hpfsnode cacheing. 53 */ 54 static LIST_HEAD(hphashhead, hpfsnode) *hpfs_hphashtbl; 55 static u_long hpfs_hphash; /* size of hash table - 1 */ 56 #define HPNOHASH(dev, lsn) (&hpfs_hphashtbl[(minor(dev) + (lsn)) & hpfs_hphash]) 57 #ifndef NULL_SIMPLELOCKS 58 static struct lwkt_token hpfs_hphash_token; 59 #endif 60 struct lock hpfs_hphash_lock; 61 62 /* 63 * Initialize inode hash table. 64 */ 65 void 66 hpfs_hphashinit() 67 { 68 69 lockinit (&hpfs_hphash_lock, 0, "hpfs_hphashlock", 0, 0); 70 hpfs_hphashtbl = HASHINIT(desiredvnodes, M_HPFSHASH, M_WAITOK, 71 &hpfs_hphash); 72 lwkt_inittoken(&hpfs_hphash_token); 73 } 74 75 /* 76 * Use the device/inum pair to find the incore inode, and return a pointer 77 * to it. If it is in core, return it, even if it is locked. 78 */ 79 struct hpfsnode * 80 hpfs_hphashlookup(dev, ino) 81 dev_t dev; 82 lsn_t ino; 83 { 84 struct hpfsnode *hp; 85 86 lwkt_gettoken(&hpfs_hphash_token); 87 for (hp = HPNOHASH(dev, ino)->lh_first; hp; hp = hp->h_hash.le_next) 88 if (ino == hp->h_no && dev == hp->h_dev) 89 break; 90 lwkt_reltoken(&hpfs_hphash_token); 91 92 return (hp); 93 } 94 95 #if 0 96 struct hpfsnode * 97 hpfs_hphashget(dev, ino) 98 dev_t dev; 99 lsn_t ino; 100 { 101 struct hpfsnode *hp; 102 103 loop: 104 lwkt_gettoken(&hpfs_hphash_token); 105 for (hp = HPNOHASH(dev, ino)->lh_first; hp; hp = hp->h_hash.le_next) { 106 if (ino == hp->h_no && dev == hp->h_dev) { 107 LOCKMGR(&hp->h_intlock, LK_EXCLUSIVE | LK_INTERLOCK, &hpfs_hphash_token, NULL); 108 return (hp); 109 } 110 } 111 lwkt_reltoken(&hpfs_hphash_token); 112 return (hp); 113 } 114 #endif 115 116 struct vnode * 117 hpfs_hphashvget(dev, ino, p) 118 dev_t dev; 119 lsn_t ino; 120 struct proc *p; 121 { 122 struct hpfsnode *hp; 123 struct vnode *vp; 124 int gen; 125 126 gen = lwkt_gettoken(&hpfs_hphash_token); 127 loop: 128 for (hp = HPNOHASH(dev, ino)->lh_first; hp; hp = hp->h_hash.le_next) { 129 if (ino == hp->h_no && dev == hp->h_dev) { 130 vp = HPTOV(hp); 131 lwkt_gettoken (&vp->v_interlock); 132 if (lwkt_gentoken(&hpfs_hphash_token, &gen)) 133 goto loop; 134 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, p)) { 135 gen = lwkt_regettoken(&hpfs_hphash_token); 136 goto loop; 137 } 138 lwkt_reltoken(&hpfs_hphash_token); 139 return (vp); 140 } 141 } 142 lwkt_reltoken(&hpfs_hphash_token); 143 return (NULLVP); 144 } 145 146 /* 147 * Insert the hpfsnode into the hash table. 148 */ 149 void 150 hpfs_hphashins(hp) 151 struct hpfsnode *hp; 152 { 153 struct hphashhead *hpp; 154 155 lwkt_gettoken(&hpfs_hphash_token); 156 hpp = HPNOHASH(hp->h_dev, hp->h_no); 157 hp->h_flag |= H_HASHED; 158 LIST_INSERT_HEAD(hpp, hp, h_hash); 159 lwkt_reltoken(&hpfs_hphash_token); 160 } 161 162 /* 163 * Remove the inode from the hash table. 164 */ 165 void 166 hpfs_hphashrem(hp) 167 struct hpfsnode *hp; 168 { 169 lwkt_gettoken(&hpfs_hphash_token); 170 if (hp->h_flag & H_HASHED) { 171 hp->h_flag &= ~H_HASHED; 172 LIST_REMOVE(hp, h_hash); 173 #ifdef DIAGNOSTIC 174 hp->h_hash.le_next = NULL; 175 hp->h_hash.le_prev = NULL; 176 #endif 177 } 178 lwkt_reltoken(&hpfs_hphash_token); 179 } 180