1656a89476
Implement cd9660_blkatoff() and use it. Reduce lots of multiplies and divides to shifts. Make some macros look more like UFS. Make isodirino() return the inumber rather than poke it into the abyss.
105 lines
3.4 KiB
C
105 lines
3.4 KiB
C
/* $NetBSD: cd9660_bmap.c,v 1.4 1994/07/19 14:14:08 mycroft Exp $ */
|
|
|
|
/*-
|
|
* 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/param.h>
|
|
#include <sys/namei.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/file.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;
|
|
} */ *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;
|
|
}
|
|
|
|
return (0);
|
|
}
|