170 lines
4.5 KiB
C
170 lines
4.5 KiB
C
/*-
|
|
* Copyright (c) 1982, 1986, 1989, 1991, 1993, 1995
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* @(#)ufs_ihash.c 8.7 (Berkeley) 5/17/95
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/mutex.h>
|
|
|
|
#include <gnu/ext2fs/inode.h>
|
|
#include <gnu/ext2fs/ext2_extern.h>
|
|
|
|
static MALLOC_DEFINE(M_EXT2IHASH, "EXT2 ihash", "EXT2 Inode hash tables");
|
|
/*
|
|
* Structures associated with inode cacheing.
|
|
*/
|
|
static LIST_HEAD(ihashhead, inode) *ihashtbl;
|
|
static u_long ihash; /* size of hash table - 1 */
|
|
#define INOHASH(device, inum) (&ihashtbl[(minor(device) + (inum)) & ihash])
|
|
static struct mtx ext2_ihash_mtx;
|
|
|
|
/*
|
|
* Initialize inode hash table.
|
|
*/
|
|
void
|
|
ext2_ihashinit()
|
|
{
|
|
|
|
KASSERT(ihashtbl == NULL, ("ext2_ihashinit called twice"));
|
|
ihashtbl = hashinit(desiredvnodes, M_EXT2IHASH, &ihash);
|
|
mtx_init(&ext2_ihash_mtx, "ext2 ihash", NULL, MTX_DEF);
|
|
}
|
|
|
|
/*
|
|
* Destroy the inode hash table.
|
|
*/
|
|
void
|
|
ext2_ihashuninit()
|
|
{
|
|
|
|
hashdestroy(ihashtbl, M_EXT2IHASH, ihash);
|
|
mtx_destroy(&ext2_ihash_mtx);
|
|
}
|
|
|
|
/*
|
|
* Use the device/inum pair to find the incore inode, and return a pointer
|
|
* to it. If it is in core, return it, even if it is locked.
|
|
*/
|
|
struct vnode *
|
|
ext2_ihashlookup(dev, inum)
|
|
struct cdev *dev;
|
|
ino_t inum;
|
|
{
|
|
struct inode *ip;
|
|
|
|
mtx_lock(&ext2_ihash_mtx);
|
|
LIST_FOREACH(ip, INOHASH(dev, inum), i_hash)
|
|
if (inum == ip->i_number && dev == ip->i_dev)
|
|
break;
|
|
mtx_unlock(&ext2_ihash_mtx);
|
|
|
|
if (ip)
|
|
return (ITOV(ip));
|
|
return (NULLVP);
|
|
}
|
|
|
|
/*
|
|
* Use the device/inum pair to find the incore inode, and return a pointer
|
|
* to it. If it is in core, but locked, wait for it.
|
|
*/
|
|
int
|
|
ext2_ihashget(dev, inum, flags, vpp)
|
|
struct cdev *dev;
|
|
ino_t inum;
|
|
int flags;
|
|
struct vnode **vpp;
|
|
{
|
|
struct thread *td = curthread; /* XXX */
|
|
struct inode *ip;
|
|
struct vnode *vp;
|
|
int error;
|
|
|
|
*vpp = NULL;
|
|
loop:
|
|
mtx_lock(&ext2_ihash_mtx);
|
|
LIST_FOREACH(ip, INOHASH(dev, inum), i_hash) {
|
|
if (inum == ip->i_number && dev == ip->i_dev) {
|
|
vp = ITOV(ip);
|
|
mtx_lock(&vp->v_interlock);
|
|
mtx_unlock(&ext2_ihash_mtx);
|
|
error = vget(vp, flags | LK_INTERLOCK, td);
|
|
if (error == ENOENT)
|
|
goto loop;
|
|
if (error)
|
|
return (error);
|
|
*vpp = vp;
|
|
return (0);
|
|
}
|
|
}
|
|
mtx_unlock(&ext2_ihash_mtx);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Insert the inode into the hash table, and return it locked.
|
|
*/
|
|
void
|
|
ext2_ihashins(ip)
|
|
struct inode *ip;
|
|
{
|
|
struct thread *td = curthread; /* XXX */
|
|
struct ihashhead *ipp;
|
|
|
|
/* lock the inode, then put it on the appropriate hash list */
|
|
vn_lock(ITOV(ip), LK_EXCLUSIVE | LK_RETRY, td);
|
|
|
|
mtx_lock(&ext2_ihash_mtx);
|
|
ipp = INOHASH(ip->i_dev, ip->i_number);
|
|
LIST_INSERT_HEAD(ipp, ip, i_hash);
|
|
ip->i_flag |= IN_HASHED;
|
|
mtx_unlock(&ext2_ihash_mtx);
|
|
}
|
|
|
|
/*
|
|
* Remove the inode from the hash table.
|
|
*/
|
|
void
|
|
ext2_ihashrem(ip)
|
|
struct inode *ip;
|
|
{
|
|
mtx_lock(&ext2_ihash_mtx);
|
|
if (ip->i_flag & IN_HASHED) {
|
|
ip->i_flag &= ~IN_HASHED;
|
|
LIST_REMOVE(ip, i_hash);
|
|
}
|
|
mtx_unlock(&ext2_ihash_mtx);
|
|
}
|