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/* $OpenBSD: ffs_subr.c,v 1.16 2005/07/03 20:14:02 drahn Exp $ */
/* $NetBSD: ffs_subr.c,v 1.6 1996/03/17 02:16:23 christos Exp $ */
/*
* Copyright (c) 1982, 1986, 1989, 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. 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.
*
* @(#)ffs_subr.c 8.2 (Berkeley) 9/21/93
*/
#include <sys/param.h>
#include <ufs/ffs/fs.h>
#ifdef _KERNEL
#include <sys/systm.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/buf.h>
#include <ufs/ufs/quota.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/ufs_extern.h>
#include <ufs/ffs/ffs_extern.h>
/*
* Return buffer with the contents of block "offset" from the beginning of
* directory "ip". If "res" is non-zero, fill it in with a pointer to the
* remaining space in the directory.
*/
int
ffs_bufatoff(struct inode *ip, off_t offset, char **res, struct buf **bpp)
{
struct fs *fs;
struct vnode *vp;
struct buf *bp;
daddr_t lbn;
int bsize, error;
vp = ITOV(ip);
fs = ip->i_fs;
lbn = lblkno(fs, offset);
bsize = blksize(fs, ip, lbn);
*bpp = NULL;
if ((error = bread(vp, lbn, bsize, NOCRED, &bp)) != 0) {
brelse(bp);
return (error);
}
if (res)
*res = (char *)bp->b_data + blkoff(fs, offset);
*bpp = bp;
return (0);
}
#else
/* Prototypes for userland */
void ffs_fragacct(struct fs *, int, int32_t[], int);
int ffs_isfreeblock(struct fs *, unsigned char *, daddr_t);
int ffs_isblock(struct fs *, unsigned char *, daddr_t);
void ffs_clrblock(struct fs *, u_char *, daddr_t);
void ffs_setblock(struct fs *, unsigned char *, daddr_t);
__dead void panic(const char *, ...);
#endif
/*
* Update the frsum fields to reflect addition or deletion
* of some frags.
*/
void
ffs_fragacct(fs, fragmap, fraglist, cnt)
struct fs *fs;
int fragmap;
int32_t fraglist[];
int cnt;
{
int inblk;
register int field, subfield;
register int siz, pos;
inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1;
fragmap <<= 1;
for (siz = 1; siz < fs->fs_frag; siz++) {
if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0)
continue;
field = around[siz];
subfield = inside[siz];
for (pos = siz; pos <= fs->fs_frag; pos++) {
if ((fragmap & field) == subfield) {
fraglist[siz] += cnt;
pos += siz;
field <<= siz;
subfield <<= siz;
}
field <<= 1;
subfield <<= 1;
}
}
}
#if defined(_KERNEL) && defined(DIAGNOSTIC)
void
ffs_checkoverlap(bp, ip)
struct buf *bp;
struct inode *ip;
{
register struct buf *ebp, *ep;
register daddr_t start, last;
struct vnode *vp;
ebp = &buf[nbuf];
start = bp->b_blkno;
last = start + btodb(bp->b_bcount) - 1;
for (ep = buf; ep < ebp; ep++) {
if (ep == bp || (ep->b_flags & B_INVAL) ||
ep->b_vp == NULLVP)
continue;
if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL))
continue;
if (vp != ip->i_devvp)
continue;
/* look for overlap */
if (ep->b_bcount == 0 || ep->b_blkno > last ||
ep->b_blkno + btodb(ep->b_bcount) <= start)
continue;
vprint("Disk overlap", vp);
(void)printf("\tstart %d, end %d overlap start %d, end %ld\n",
start, last, ep->b_blkno,
ep->b_blkno + btodb(ep->b_bcount) - 1);
panic("Disk buffer overlap");
}
}
#endif /* DIAGNOSTIC */
/*
* block operations
*
* check if a block is available
*/
int
ffs_isblock(fs, cp, h)
struct fs *fs;
unsigned char *cp;
daddr_t h;
{
unsigned char mask;
switch ((int)fs->fs_frag) {
case 8:
return (cp[h] == 0xff);
case 4:
mask = 0x0f << ((h & 0x1) << 2);
return ((cp[h >> 1] & mask) == mask);
case 2:
mask = 0x03 << ((h & 0x3) << 1);
return ((cp[h >> 2] & mask) == mask);
case 1:
mask = 0x01 << (h & 0x7);
return ((cp[h >> 3] & mask) == mask);
default:
panic("ffs_isblock");
}
}
/*
* take a block out of the map
*/
void
ffs_clrblock(fs, cp, h)
struct fs *fs;
u_char *cp;
daddr_t h;
{
switch ((int)fs->fs_frag) {
case 8:
cp[h] = 0;
return;
case 4:
cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
return;
case 2:
cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
return;
case 1:
cp[h >> 3] &= ~(0x01 << (h & 0x7));
return;
default:
panic("ffs_clrblock");
}
}
/*
* put a block into the map
*/
void
ffs_setblock(fs, cp, h)
struct fs *fs;
unsigned char *cp;
daddr_t h;
{
switch ((int)fs->fs_frag) {
case 8:
cp[h] = 0xff;
return;
case 4:
cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
return;
case 2:
cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
return;
case 1:
cp[h >> 3] |= (0x01 << (h & 0x7));
return;
default:
panic("ffs_setblock");
}
}
/*
* check if a block is free
*/
int
ffs_isfreeblock(fs, cp, h)
struct fs *fs;
unsigned char *cp;
daddr_t h;
{
switch ((int)fs->fs_frag) {
case 8:
return (cp[h] == 0);
case 4:
return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0);
case 2:
return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0);
case 1:
return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0);
default:
panic("ffs_isfreeblock");
}
}
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