| 1 | /* $NetBSD: ntfs_ihash.c,v 1.11 2015/02/20 17:08:13 maxv 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 1.11 2015/02/20 17:08:13 maxv 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/mount.h> |
| 44 | #include <sys/mallocvar.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(void) |
| 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(void) |
| 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(void) |
| 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_t dev, ino_t inum) |
| 118 | { |
| 119 | struct ntnode *ip; |
| 120 | struct nthashhead *ipp; |
| 121 | |
| 122 | mutex_enter(&ntfs_nthash_lock); |
| 123 | ipp = &ntfs_nthashtbl[NTNOHASH(dev, inum)]; |
| 124 | LIST_FOREACH(ip, ipp, i_hash) { |
| 125 | if (inum == ip->i_number && dev == ip->i_dev) |
| 126 | break; |
| 127 | } |
| 128 | mutex_exit(&ntfs_nthash_lock); |
| 129 | |
| 130 | return (ip); |
| 131 | } |
| 132 | |
| 133 | /* |
| 134 | * Insert the ntnode into the hash table. |
| 135 | */ |
| 136 | void |
| 137 | ntfs_nthashins(struct ntnode *ip) |
| 138 | { |
| 139 | struct nthashhead *ipp; |
| 140 | |
| 141 | mutex_enter(&ntfs_nthash_lock); |
| 142 | ipp = &ntfs_nthashtbl[NTNOHASH(ip->i_dev, ip->i_number)]; |
| 143 | LIST_INSERT_HEAD(ipp, ip, i_hash); |
| 144 | ip->i_flag |= IN_HASHED; |
| 145 | mutex_exit(&ntfs_nthash_lock); |
| 146 | } |
| 147 | |
| 148 | /* |
| 149 | * Remove the inode from the hash table. |
| 150 | */ |
| 151 | void |
| 152 | ntfs_nthashrem(struct ntnode *ip) |
| 153 | { |
| 154 | mutex_enter(&ntfs_nthash_lock); |
| 155 | if (ip->i_flag & IN_HASHED) { |
| 156 | ip->i_flag &= ~IN_HASHED; |
| 157 | LIST_REMOVE(ip, i_hash); |
| 158 | } |
| 159 | mutex_exit(&ntfs_nthash_lock); |
| 160 | } |
| 161 | |