ext2fs_subr.c revision 1.9 1 /* $NetBSD: ext2fs_subr.c,v 1.9 2003/01/25 18:12:31 tron 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/cdefs.h>
41 __KERNEL_RCSID(0, "$NetBSD: ext2fs_subr.c,v 1.9 2003/01/25 18:12:31 tron Exp $");
42
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/vnode.h>
46 #include <sys/buf.h>
47 #include <sys/inttypes.h>
48 #include <ufs/ufs/inode.h>
49 #include <ufs/ext2fs/ext2fs.h>
50 #include <ufs/ext2fs/ext2fs_extern.h>
51
52 /*
53 * Return buffer with the contents of block "offset" from the beginning of
54 * directory "ip". If "res" is non-zero, fill it in with a pointer to the
55 * remaining space in the directory.
56 */
57 int
58 ext2fs_blkatoff(v)
59 void *v;
60 {
61 struct vop_blkatoff_args /* {
62 struct vnode *a_vp;
63 off_t a_offset;
64 char **a_res;
65 struct buf **a_bpp;
66 } */ *ap = v;
67 struct inode *ip;
68 struct m_ext2fs *fs;
69 struct buf *bp;
70 daddr_t lbn;
71 int error;
72
73 ip = VTOI(ap->a_vp);
74 fs = ip->i_e2fs;
75 lbn = lblkno(fs, ap->a_offset);
76
77 *ap->a_bpp = NULL;
78 if ((error = bread(ap->a_vp, lbn, fs->e2fs_bsize, NOCRED, &bp)) != 0) {
79 brelse(bp);
80 return (error);
81 }
82 if (ap->a_res)
83 *ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset);
84 *ap->a_bpp = bp;
85 return (0);
86 }
87
88 #ifdef DIAGNOSTIC
89 void
90 ext2fs_checkoverlap(bp, ip)
91 struct buf *bp;
92 struct inode *ip;
93 {
94 struct buf *ebp, *ep;
95 daddr_t start, last;
96 struct vnode *vp;
97
98 ebp = &buf[nbuf];
99 start = bp->b_blkno;
100 last = start + btodb(bp->b_bcount) - 1;
101 for (ep = buf; ep < ebp; ep++) {
102 if (ep == bp || (ep->b_flags & B_INVAL) ||
103 ep->b_vp == NULLVP)
104 continue;
105 if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL))
106 continue;
107 if (vp != ip->i_devvp)
108 continue;
109 /* look for overlap */
110 if (ep->b_bcount == 0 || ep->b_blkno > last ||
111 ep->b_blkno + btodb(ep->b_bcount) <= start)
112 continue;
113 vprint("Disk overlap", vp);
114 printf("\tstart %" PRId64 ", end %" PRId64 " overlap start "
115 "%" PRId64 ", end %" PRId64 "\n",
116 start, last, ep->b_blkno,
117 ep->b_blkno + btodb(ep->b_bcount) - 1);
118 panic("Disk buffer overlap");
119 }
120 }
121 #endif
122