109 lines
3.4 KiB
C
109 lines
3.4 KiB
C
/*-
|
|
* Copyright (c) 1994
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley
|
|
* by Pace Willisson (pace@blitz.com). The Rock Ridge Extension
|
|
* Support code is derived from software contributed to Berkeley
|
|
* by Atsushi Murai (amurai@spec.co.jp).
|
|
*
|
|
* 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.
|
|
*
|
|
* @(#)cd9660_bmap.c 8.3 (Berkeley) 1/23/94
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/mount.h>
|
|
|
|
#include <isofs/cd9660/iso.h>
|
|
#include <isofs/cd9660/cd9660_node.h>
|
|
|
|
/*
|
|
* Bmap converts a the logical block number of a file to its physical block
|
|
* number on the disk. The conversion is done by using the logical block
|
|
* number to index into the data block (extent) for the file.
|
|
*/
|
|
int
|
|
cd9660_bmap(ap)
|
|
struct vop_bmap_args /* {
|
|
struct vnode *a_vp;
|
|
daddr_t a_bn;
|
|
struct vnode **a_vpp;
|
|
daddr_t *a_bnp;
|
|
int *a_runp;
|
|
int *a_runb;
|
|
} */ *ap;
|
|
{
|
|
struct iso_node *ip = VTOI(ap->a_vp);
|
|
daddr_t lblkno = ap->a_bn;
|
|
int bshift;
|
|
|
|
/*
|
|
* Check for underlying vnode requests and ensure that logical
|
|
* to physical mapping is requested.
|
|
*/
|
|
if (ap->a_vpp != NULL)
|
|
*ap->a_vpp = ip->i_devvp;
|
|
if (ap->a_bnp == NULL)
|
|
return (0);
|
|
|
|
/*
|
|
* Compute the requested block number
|
|
*/
|
|
bshift = ip->i_mnt->im_bshift;
|
|
*ap->a_bnp = (ip->iso_start + lblkno) << (bshift - DEV_BSHIFT);
|
|
|
|
/*
|
|
* Determine maximum number of readahead blocks following the
|
|
* requested block.
|
|
*/
|
|
if (ap->a_runp) {
|
|
int nblk;
|
|
|
|
nblk = (ip->i_size >> bshift) - (lblkno + 1);
|
|
if (nblk <= 0)
|
|
*ap->a_runp = 0;
|
|
else if (nblk >= (MAXBSIZE >> bshift))
|
|
*ap->a_runp = (MAXBSIZE >> bshift) - 1;
|
|
else
|
|
*ap->a_runp = nblk;
|
|
}
|
|
|
|
if (ap->a_runb) {
|
|
*ap->a_runb = 0;
|
|
}
|
|
|
|
return 0;
|
|
}
|