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29 * @(#)ufs_ihash.c 8.7 (Berkeley) 5/17/95
30 * $FreeBSD: src/sys/ufs/ufs/ufs_ihash.c,v 1.20 1999/08/28 00:52:29 peter Exp $
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
37 #include <sys/vnode.h>
38 #include <sys/malloc.h>
44 #include "ext2_extern.h"
46 static MALLOC_DEFINE(M_EXT2IHASH, "EXT2 ihash", "EXT2 Inode hash tables");
48 * Structures associated with inode cacheing.
50 static struct inode **ext2_ihashtbl;
51 static u_long ext2_ihash; /* size of hash table - 1 */
52 static struct lwkt_token ext2_ihash_token;
54 #define INOHASH(device, inum) (&ext2_ihashtbl[(minor(device) + (inum)) & ext2_ihash])
57 * Initialize inode hash table.
63 while (ext2_ihash < desiredvnodes)
65 ext2_ihashtbl = kmalloc(sizeof(void *) * ext2_ihash, M_EXT2IHASH, M_WAITOK|M_ZERO);
67 lwkt_token_init(&ext2_ihash_token, "ext2ihash");
71 ext2_uninit(struct vfsconf *vfc)
73 lwkt_gettoken(&ext2_ihash_token);
75 kfree(ext2_ihashtbl, M_EXT2IHASH);
76 lwkt_reltoken(&ext2_ihash_token);
81 * Use the device/inum pair to find the incore inode, and return a pointer
82 * to it. If it is in core, return it, even if it is locked.
85 ext2_ihashlookup(cdev_t dev, ino_t inum)
89 lwkt_gettoken(&ext2_ihash_token);
90 for (ip = *INOHASH(dev, inum); ip; ip = ip->i_next) {
91 if (inum == ip->i_number && dev == ip->i_dev)
94 lwkt_reltoken(&ext2_ihash_token);
101 * Use the device/inum pair to find the incore inode, and return a pointer
102 * to it. If it is in core, but locked, wait for it.
104 * Note that the serializing tokens do not prevent other processes from
105 * playing with the data structure being protected while we are blocked.
106 * They do protect us from preemptive interrupts which might try to
107 * play with the protected data structure.
110 ext2_ihashget(cdev_t dev, ino_t inum)
115 lwkt_gettoken(&ext2_ihash_token);
117 for (ip = *INOHASH(dev, inum); ip; ip = ip->i_next) {
118 if (inum != ip->i_number || dev != ip->i_dev)
121 if (vget(vp, LK_EXCLUSIVE))
124 * We must check to see if the inode has been ripped
125 * out from under us after blocking.
127 for (ip = *INOHASH(dev, inum); ip; ip = ip->i_next) {
128 if (inum == ip->i_number && dev == ip->i_dev)
131 if (ip == NULL || ITOV(ip) != vp) {
135 lwkt_reltoken(&ext2_ihash_token);
138 lwkt_reltoken(&ext2_ihash_token);
143 * Check to see if an inode is in the hash table. This is used to interlock
144 * file free operations to ensure that the vnode is not reused due to a
145 * reallocate of its inode number before we have had a chance to recycle it.
148 ext2_ihashcheck(cdev_t dev, ino_t inum)
152 lwkt_gettoken(&ext2_ihash_token);
153 for (ip = *INOHASH(dev, inum); ip; ip = ip->i_next) {
154 if (inum == ip->i_number && dev == ip->i_dev)
157 lwkt_reltoken(&ext2_ihash_token);
162 * Insert the inode into the hash table, and return it locked.
165 ext2_ihashins(struct inode *ip)
170 KKASSERT((ip->i_flag & IN_HASHED) == 0);
171 lwkt_gettoken(&ext2_ihash_token);
172 ipp = INOHASH(ip->i_dev, ip->i_number);
173 while ((iq = *ipp) != NULL) {
174 if (ip->i_dev == iq->i_dev && ip->i_number == iq->i_number) {
175 lwkt_reltoken(&ext2_ihash_token);
182 ip->i_flag |= IN_HASHED;
183 lwkt_reltoken(&ext2_ihash_token);
188 * Remove the inode from the hash table.
191 ext2_ihashrem(struct inode *ip)
196 lwkt_gettoken(&ext2_ihash_token);
197 if (ip->i_flag & IN_HASHED) {
198 ipp = INOHASH(ip->i_dev, ip->i_number);
199 while ((iq = *ipp) != NULL) {
207 ip->i_flag &= ~IN_HASHED;
209 lwkt_reltoken(&ext2_ihash_token);