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/*
* 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. 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.
*
* @(#)ffs_subr.c 8.2 (Berkeley) 9/21/93
*/
#include "ufs.h"
#include "fs.h"
#if 0 /* Not needed in GNU Hurd ufs. */
/*
* 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_blkatoff(ap)
struct vop_blkatoff_args /* {
struct vnode *a_vp;
off_t a_offset;
char **a_res;
struct buf **a_bpp;
} */ *ap;
{
struct inode *ip;
register struct fs *fs;
struct buf *bp;
daddr_t lbn;
int bsize, error;
ip = VTOI(ap->a_vp);
fs = ip->i_fs;
lbn = lblkno(fs, ap->a_offset);
bsize = blksize(fs, ip, lbn);
*ap->a_bpp = NULL;
if (error = bread(ap->a_vp, lbn, bsize, NOCRED, &bp)) {
brelse(bp);
return (error);
}
if (ap->a_res)
*ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset);
*ap->a_bpp = bp;
return (0);
}
#endif /* 0 */
/*
* Update the frsum fields to reflect addition or deletion
* of some frags.
*/
void
ffs_fragacct(fs, fragmap, fraglist, cnt)
struct fs *fs;
int fragmap;
long 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 0 /* Not needed in GNU Hurd ufs. */
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 %d\n",
start, last, ep->b_blkno,
ep->b_blkno + btodb(ep->b_bcount) - 1);
panic("Disk buffer overlap");
}
}
#endif /* 0 */
/*
* 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");
}
}
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