freebsd-dev/sys/ntfs/ntfs_ihash.c

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/* $NetBSD: ntfs_ihash.c,v 1.5 1999/09/30 16:56:40 jdolecek Exp $ */
/*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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
1999-08-28 01:08:13 +00:00
* $FreeBSD$
*/
#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/mount.h>
#include <ntfs/ntfs.h>
#include <ntfs/ntfs_inode.h>
#include <ntfs/ntfs_ihash.h>
MALLOC_DEFINE(M_NTFSNTHASH, "NTFS nthash", "NTFS ntnode hash tables");
/*
* Structures associated with inode cacheing.
*/
static LIST_HEAD(nthashhead, ntnode) *ntfs_nthashtbl;
static u_long ntfs_nthash; /* size of hash table - 1 */
Divorce "dev_t" from the "major|minor" bitmap, which is now called udev_t in the kernel but still called dev_t in userland. Provide functions to manipulate both types: major() umajor() minor() uminor() makedev() umakedev() dev2udev() udev2dev() For now they're functions, they will become in-line functions after one of the next two steps in this process. Return major/minor/makedev to macro-hood for userland. Register a name in cdevsw[] for the "filedescriptor" driver. In the kernel the udev_t appears in places where we have the major/minor number combination, (ie: a potential device: we may not have the driver nor the device), like in inodes, vattr, cdevsw registration and so on, whereas the dev_t appears where we carry around a reference to a actual device. In the future the cdevsw and the aliased-from vnode will be hung directly from the dev_t, along with up to two softc pointers for the device driver and a few houskeeping bits. This will essentially replace the current "alias" check code (same buck, bigger bang). A little stunt has been provided to try to catch places where the wrong type is being used (dev_t vs udev_t), if you see something not working, #undef DEVT_FASCIST in kern/kern_conf.c and see if it makes a difference. If it does, please try to track it down (many hands make light work) or at least try to reproduce it as simply as possible, and describe how to do that. Without DEVT_FASCIST I belive this patch is a no-op. Stylistic/posixoid comments about the userland view of the <sys/*.h> files welcome now, from userland they now contain the end result. Next planned step: make all dev_t's refer to the same devsw[] which means convert BLK's to CHR's at the perimeter of the vnodes and other places where they enter the game (bootdev, mknod, sysctl).
1999-05-11 19:55:07 +00:00
#define NTNOHASH(device, inum) (&ntfs_nthashtbl[(minor(device) + (inum)) & ntfs_nthash])
#ifndef NULL_SIMPLELOCKS
static struct simplelock ntfs_nthash_slock;
#endif
struct lock ntfs_hashlock;
/*
* Initialize inode hash table.
*/
void
ntfs_nthashinit()
{
lockinit(&ntfs_hashlock, PINOD, "ntfs_nthashlock", 0, 0);
ntfs_nthashtbl = HASHINIT(desiredvnodes, M_NTFSNTHASH, M_WAITOK,
&ntfs_nthash);
simple_lock_init(&ntfs_nthash_slock);
}
/*
* 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 ntnode *
ntfs_nthashlookup(dev, inum)
dev_t dev;
ino_t inum;
{
struct ntnode *ip;
simple_lock(&ntfs_nthash_slock);
for (ip = NTNOHASH(dev, inum)->lh_first; ip; ip = ip->i_hash.le_next)
if (inum == ip->i_number && dev == ip->i_dev)
break;
simple_unlock(&ntfs_nthash_slock);
return (ip);
}
/*
* Insert the ntnode into the hash table.
*/
void
ntfs_nthashins(ip)
struct ntnode *ip;
{
struct nthashhead *ipp;
simple_lock(&ntfs_nthash_slock);
ipp = NTNOHASH(ip->i_dev, ip->i_number);
LIST_INSERT_HEAD(ipp, ip, i_hash);
ip->i_flag |= IN_HASHED;
simple_unlock(&ntfs_nthash_slock);
}
/*
* Remove the inode from the hash table.
*/
void
ntfs_nthashrem(ip)
struct ntnode *ip;
{
simple_lock(&ntfs_nthash_slock);
if (ip->i_flag & IN_HASHED) {
ip->i_flag &= ~IN_HASHED;
LIST_REMOVE(ip, i_hash);
#ifdef DIAGNOSTIC
ip->i_hash.le_next = NULL;
ip->i_hash.le_prev = NULL;
#endif
}
simple_unlock(&ntfs_nthash_slock);
}