diff options
Diffstat (limited to 'sys/gnu/ext2fs/ext2_ihash.c')
| -rw-r--r-- | sys/gnu/ext2fs/ext2_ihash.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/sys/gnu/ext2fs/ext2_ihash.c b/sys/gnu/ext2fs/ext2_ihash.c new file mode 100644 index 0000000..4a37c90 --- /dev/null +++ b/sys/gnu/ext2fs/ext2_ihash.c @@ -0,0 +1,154 @@ +/* + * Copyright (c) 1982, 1986, 1989, 1991, 1993 + * 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 8.4 (Berkeley) 12/30/93 + */ + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/vnode.h> +#include <sys/malloc.h> +#include <sys/proc.h> + +#include <ufs/ufs/quota.h> +#include <ufs/ufs/inode.h> +#include <ufs/ufs/ufs_extern.h> + +/* + * Structures associated with inode cacheing. + */ +struct inode **ihashtbl; +u_long ihash; /* size of hash table - 1 */ +#define INOHASH(device, inum) (((device) + (inum)) & ihash) + +/* + * Initialize inode hash table. + */ +void +ufs_ihashinit() +{ + + ihashtbl = hashinit(desiredvnodes, M_UFSMNT, &ihash); +} + +/* + * 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 * +ufs_ihashlookup(device, inum) + dev_t device; + ino_t inum; +{ + register struct inode *ip; + + for (ip = ihashtbl[INOHASH(device, inum)];; ip = ip->i_next) { + if (ip == NULL) + return (NULL); + if (inum == ip->i_number && device == ip->i_dev) + return (ITOV(ip)); + } + /* NOTREACHED */ +} + +/* + * 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. + */ +struct vnode * +ufs_ihashget(device, inum) + dev_t device; + ino_t inum; +{ + register struct inode *ip; + struct vnode *vp; + + for (;;) + for (ip = ihashtbl[INOHASH(device, inum)];; ip = ip->i_next) { + if (ip == NULL) + return (NULL); + if (inum == ip->i_number && device == ip->i_dev) { + if (ip->i_flag & IN_LOCKED) { + ip->i_flag |= IN_WANTED; + sleep(ip, PINOD); + break; + } + vp = ITOV(ip); + if (!vget(vp, 1)) + return (vp); + break; + } + } + /* NOTREACHED */ +} + +/* + * Insert the inode into the hash table, and return it locked. + */ +void +ufs_ihashins(ip) + struct inode *ip; +{ + struct inode **ipp, *iq; + + ipp = &ihashtbl[INOHASH(ip->i_dev, ip->i_number)]; + if (iq = *ipp) + iq->i_prev = &ip->i_next; + ip->i_next = iq; + ip->i_prev = ipp; + *ipp = ip; + if (ip->i_flag & IN_LOCKED) + panic("ufs_ihashins: already locked"); + if (curproc) + ip->i_lockholder = curproc->p_pid; + else + ip->i_lockholder = -1; + ip->i_flag |= IN_LOCKED; +} + +/* + * Remove the inode from the hash table. + */ +void +ufs_ihashrem(ip) + register struct inode *ip; +{ + register struct inode *iq; + + if (iq = ip->i_next) + iq->i_prev = ip->i_prev; + *ip->i_prev = iq; +#ifdef DIAGNOSTIC + ip->i_next = NULL; + ip->i_prev = NULL; +#endif +} |
