xref: /netbsd-src/sys/ufs/ext2fs/ext2fs_subr.c (revision 3b01aba77a7a698587faaae455bbfe740923c1f5)
1 /*	$NetBSD: ext2fs_subr.c,v 1.4 2000/03/30 12:41:11 augustss Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 Manuel Bouyer.
5  * Copyright (c) 1982, 1986, 1989, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)ffs_subr.c	8.2 (Berkeley) 9/21/93
37  * Modified for ext2fs by Manuel Bouyer.
38  */
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/vnode.h>
43 #include <sys/buf.h>
44 #include <ufs/ufs/quota.h>
45 #include <ufs/ufs/inode.h>
46 #include <ufs/ext2fs/ext2fs.h>
47 #include <ufs/ext2fs/ext2fs_extern.h>
48 
49 /*
50  * Return buffer with the contents of block "offset" from the beginning of
51  * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
52  * remaining space in the directory.
53  */
54 int
55 ext2fs_blkatoff(v)
56 	void *v;
57 {
58 	struct vop_blkatoff_args /* {
59 		struct vnode *a_vp;
60 		off_t a_offset;
61 		char **a_res;
62 		struct buf **a_bpp;
63 	} */ *ap = v;
64 	struct inode *ip;
65 	struct m_ext2fs *fs;
66 	struct buf *bp;
67 	ufs_daddr_t lbn;
68 	int error;
69 
70 	ip = VTOI(ap->a_vp);
71 	fs = ip->i_e2fs;
72 	lbn = lblkno(fs, ap->a_offset);
73 
74 	*ap->a_bpp = NULL;
75 	if ((error = bread(ap->a_vp, lbn, fs->e2fs_bsize, NOCRED, &bp)) != 0) {
76 		brelse(bp);
77 		return (error);
78 	}
79 	if (ap->a_res)
80 		*ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset);
81 	*ap->a_bpp = bp;
82 	return (0);
83 }
84 
85 #ifdef DIAGNOSTIC
86 void
87 ext2fs_checkoverlap(bp, ip)
88 	struct buf *bp;
89 	struct inode *ip;
90 {
91 	struct buf *ebp, *ep;
92 	ufs_daddr_t start, last;
93 	struct vnode *vp;
94 
95 	ebp = &buf[nbuf];
96 	start = bp->b_blkno;
97 	last = start + btodb(bp->b_bcount) - 1;
98 	for (ep = buf; ep < ebp; ep++) {
99 		if (ep == bp || (ep->b_flags & B_INVAL) ||
100 			ep->b_vp == NULLVP)
101 			continue;
102 		if (VOP_BMAP(ep->b_vp, (ufs_daddr_t)0, &vp, (ufs_daddr_t)0, NULL))
103 			continue;
104 		if (vp != ip->i_devvp)
105 			continue;
106 		/* look for overlap */
107 		if (ep->b_bcount == 0 || ep->b_blkno > last ||
108 			ep->b_blkno + btodb(ep->b_bcount) <= start)
109 			continue;
110 		vprint("Disk overlap", vp);
111 		printf("\tstart %d, end %d overlap start %d, end %ld\n",
112 			start, last, ep->b_blkno,
113 			ep->b_blkno + btodb(ep->b_bcount) - 1);
114 		panic("Disk buffer overlap");
115 	}
116 }
117 #endif
118