[apple/xnu.git] / bsd / isofs / cd9660 / cd9660_bmap.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*	$NetBSD: cd9660_bmap.c,v 1.5 1994/12/13 22:33:12 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	8.4 (Berkeley) 12/5/94
 */

#include <sys/param.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/buf.h>
#include <sys/file.h>

#include <isofs/cd9660/iso.h>
#include <isofs/cd9660/cd9660_node.h>

/*
 * Bmap converts 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);

	/*
	 * 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);
}

/* blktooff converts a logical block number to a file offset */
int
cd9660_blktooff(ap)
	struct vop_blktooff_args /* {
		struct vnode *a_vp;
		daddr_t a_lblkno;
		off_t *a_offset;    
	} */ *ap;
{
	register struct iso_node *ip;
    register struct iso_mnt *imp;

	if (ap->a_vp == NULL)
		return (EINVAL);

	ip = VTOI(ap->a_vp);
	imp = ip->i_mnt;

	*ap->a_offset = (off_t)lblktosize(imp, ap->a_lblkno);
	return (0);
}

/* offtoblk converts a file offset to a logical block number */
int
cd9660_offtoblk(ap)
struct vop_offtoblk_args /* {
	struct vnode *a_vp;
	off_t a_offset;    
	daddr_t *a_lblkno;
	} */ *ap;
{
	register struct iso_node *ip;
	register struct iso_mnt *imp;

	if (ap->a_vp == NULL)
		return (EINVAL);

	ip = VTOI(ap->a_vp);
	imp = ip->i_mnt;

	*ap->a_lblkno = (daddr_t)lblkno(imp, ap->a_offset);
	return (0);
}

int
cd9660_cmap(ap)
struct vop_cmap_args /* {
	struct vnode *a_vp;
	off_t a_offset;    
	size_t a_size;
	daddr_t *a_bpn;
	size_t *a_run;
	void *a_poff;
} */ *ap;
{
	struct iso_node *ip = VTOI(ap->a_vp);
	size_t cbytes;
	int devBlockSize = 0;

	/*
	 * Check for underlying vnode requests and ensure that logical
	 * to physical mapping is requested.
	 */
	if (ap->a_bpn == NULL)
		return (0);

	VOP_DEVBLOCKSIZE(ip->i_devvp, &devBlockSize);

	*ap->a_bpn = (daddr_t)(ip->iso_start + lblkno(ip->i_mnt, ap->a_foffset));

	/*
	 * Determine maximum number of contiguous bytes following the
	 * requested offset.
	 */
	if (ap->a_run) {
		if (ip->i_size > ap->a_foffset)
			cbytes = ip->i_size - ap->a_foffset;
		else
			cbytes = 0;

		cbytes = (cbytes + (devBlockSize - 1)) & ~(devBlockSize - 1);

		*ap->a_run = MIN(cbytes, ap->a_size);
	};

	if (ap->a_poff)
		*(int *)ap->a_poff = (long)ap->a_foffset & (devBlockSize - 1);

	return (0);	
}
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
de355530 A	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
1c79356b	11	*
de355530 A	12	* This Original Code and all software distributed under the License are
de355530 A	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
de355530 A	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
1c79356b A	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/* $NetBSD: cd9660_bmap.c,v 1.5 1994/12/13 22:33:12 mycroft Exp $ */
	23
	24	/*-
	25	* Copyright (c) 1994
	26	* The Regents of the University of California. All rights reserved.
	27	*
	28	* This code is derived from software contributed to Berkeley
	29	* by Pace Willisson (pace@blitz.com). The Rock Ridge Extension
	30	* Support code is derived from software contributed to Berkeley
	31	* by Atsushi Murai (amurai@spec.co.jp).
	32	*
	33	* Redistribution and use in source and binary forms, with or without
	34	* modification, are permitted provided that the following conditions
	35	* are met:
	36	* 1. Redistributions of source code must retain the above copyright
	37	* notice, this list of conditions and the following disclaimer.
	38	* 2. Redistributions in binary form must reproduce the above copyright
	39	* notice, this list of conditions and the following disclaimer in the
	40	* documentation and/or other materials provided with the distribution.
	41	* 3. All advertising materials mentioning features or use of this software
	42	* must display the following acknowledgement:
	43	* This product includes software developed by the University of
	44	* California, Berkeley and its contributors.
	45	* 4. Neither the name of the University nor the names of its contributors
	46	* may be used to endorse or promote products derived from this software
	47	* without specific prior written permission.
	48	*
	49	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	50	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	51	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	52	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	53	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	54	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	55	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	56	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	57	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	58	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	59	* SUCH DAMAGE.
	60	*
	61	* @(#)cd9660_bmap.c 8.4 (Berkeley) 12/5/94
	62	*/
	63
	64	#include <sys/param.h>
	65	#include <sys/vnode.h>
	66	#include <sys/mount.h>
	67	#include <sys/namei.h>
	68	#include <sys/buf.h>
	69	#include <sys/file.h>
	70
	71	#include <isofs/cd9660/iso.h>
	72	#include <isofs/cd9660/cd9660_node.h>
	73
	74	/*
	75	* Bmap converts the logical block number of a file to its physical block
	76	* number on the disk. The conversion is done by using the logical block
	77	* number to index into the data block (extent) for the file.
	78	*/
	79	int
	80	cd9660_bmap(ap)
	81	struct vop_bmap_args /* {
	82	struct vnode *a_vp;
83	daddr_t a_bn;
84	struct vnode **a_vpp;
85	daddr_t *a_bnp;
86	int *a_runp;
87	} / ap;
88	{
89	struct iso_node *ip = VTOI(ap->a_vp);
90	daddr_t lblkno = ap->a_bn;
91	int bshift;
92
93	/*
94	* Check for underlying vnode requests and ensure that logical
95	* to physical mapping is requested.
96	*/
97	if (ap->a_vpp != NULL)
98	*ap->a_vpp = ip->i_devvp;
99	if (ap->a_bnp == NULL)
100	return (0);
101
102	/*
103	* Compute the requested block number
104	*/
105	bshift = ip->i_mnt->im_bshift;
106	*ap->a_bnp = (ip->iso_start + lblkno);
107
108	/*
109	* Determine maximum number of readahead blocks following the
110	* requested block.
111	*/
112	if (ap->a_runp) {
113	int nblk;
114
115	nblk = (ip->i_size >> bshift) - (lblkno + 1);
116	if (nblk <= 0)
117	*ap->a_runp = 0;
118	else if (nblk >= (MAXBSIZE >> bshift))
119	*ap->a_runp = (MAXBSIZE >> bshift) - 1;
120	else
121	*ap->a_runp = nblk;
122	}
123
124	return (0);
125	}
126
127	/* blktooff converts a logical block number to a file offset */
128	int
129	cd9660_blktooff(ap)
130	struct vop_blktooff_args /* {
131	struct vnode *a_vp;
132	daddr_t a_lblkno;
133	off_t *a_offset;
134	} / ap;
135	{
136	register struct iso_node *ip;
137	register struct iso_mnt *imp;
138
139	if (ap->a_vp == NULL)
140	return (EINVAL);
141
142	ip = VTOI(ap->a_vp);
143	imp = ip->i_mnt;
144
145	*ap->a_offset = (off_t)lblktosize(imp, ap->a_lblkno);
146	return (0);
147	}
148
149	/* offtoblk converts a file offset to a logical block number */
150	int
151	cd9660_offtoblk(ap)
152	struct vop_offtoblk_args /* {
153	struct vnode *a_vp;
154	off_t a_offset;
155	daddr_t *a_lblkno;
156	} / ap;
157	{
158	register struct iso_node *ip;
159	register struct iso_mnt *imp;
160
161	if (ap->a_vp == NULL)
162	return (EINVAL);
163
164	ip = VTOI(ap->a_vp);
165	imp = ip->i_mnt;
166
167	*ap->a_lblkno = (daddr_t)lblkno(imp, ap->a_offset);
168	return (0);
169	}
170
171	int
172	cd9660_cmap(ap)
173	struct vop_cmap_args /* {
174	struct vnode *a_vp;
175	off_t a_offset;
176	size_t a_size;
177	daddr_t *a_bpn;
178	size_t *a_run;
179	void *a_poff;
180	} / ap;
181	{
182	struct iso_node *ip = VTOI(ap->a_vp);
183	size_t cbytes;
184	int devBlockSize = 0;
185
186	/*
187	* Check for underlying vnode requests and ensure that logical
188	* to physical mapping is requested.
189	*/
190	if (ap->a_bpn == NULL)
191	return (0);
192
193	VOP_DEVBLOCKSIZE(ip->i_devvp, &devBlockSize);
194
195	*ap->a_bpn = (daddr_t)(ip->iso_start + lblkno(ip->i_mnt, ap->a_foffset));
196
197	/*
198	* Determine maximum number of contiguous bytes following the
199	* requested offset.
200	*/
201	if (ap->a_run) {
202	if (ip->i_size > ap->a_foffset)
203	cbytes = ip->i_size - ap->a_foffset;
204	else
205	cbytes = 0;
206
207	cbytes = (cbytes + (devBlockSize - 1)) & ~(devBlockSize - 1);
208
209	*ap->a_run = MIN(cbytes, ap->a_size);
210	};
211
212	if (ap->a_poff)
213	(int )ap->a_poff = (long)ap->a_foffset & (devBlockSize - 1);
214
215	return (0);
216	}
217