xref: /netbsd-src/sys/ufs/ext2fs/ext2fs_subr.c (revision d20841bb642898112fe68f0ad3f7b26dddf56f07)
1 /*	$NetBSD: ext2fs_subr.c,v 1.12 2003/12/30 12:33:24 pk Exp $	*/
2 
3 /*
4  * Copyright (c) 1982, 1986, 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)ffs_subr.c	8.2 (Berkeley) 9/21/93
32  * Modified for ext2fs by Manuel Bouyer.
33  */
34 
35 /*
36  * Copyright (c) 1997 Manuel Bouyer.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. All advertising materials mentioning features or use of this software
47  *    must display the following acknowledgement:
48  *	This product includes software developed by Manuel Bouyer.
49  * 4. The name of the author may not be used to endorse or promote products
50  *    derived from this software without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  *
64  *	@(#)ffs_subr.c	8.2 (Berkeley) 9/21/93
65  * Modified for ext2fs by Manuel Bouyer.
66  */
67 
68 #include <sys/cdefs.h>
69 __KERNEL_RCSID(0, "$NetBSD: ext2fs_subr.c,v 1.12 2003/12/30 12:33:24 pk Exp $");
70 
71 #include <sys/param.h>
72 #include <sys/systm.h>
73 #include <sys/vnode.h>
74 #include <sys/buf.h>
75 #include <sys/inttypes.h>
76 #include <ufs/ufs/inode.h>
77 #include <ufs/ext2fs/ext2fs.h>
78 #include <ufs/ext2fs/ext2fs_extern.h>
79 
80 /*
81  * Return buffer with the contents of block "offset" from the beginning of
82  * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
83  * remaining space in the directory.
84  */
85 int
86 ext2fs_blkatoff(v)
87 	void *v;
88 {
89 	struct vop_blkatoff_args /* {
90 		struct vnode *a_vp;
91 		off_t a_offset;
92 		char **a_res;
93 		struct buf **a_bpp;
94 	} */ *ap = v;
95 	struct inode *ip;
96 	struct m_ext2fs *fs;
97 	struct buf *bp;
98 	daddr_t lbn;
99 	int error;
100 
101 	ip = VTOI(ap->a_vp);
102 	fs = ip->i_e2fs;
103 	lbn = lblkno(fs, ap->a_offset);
104 
105 	*ap->a_bpp = NULL;
106 	if ((error = bread(ap->a_vp, lbn, fs->e2fs_bsize, NOCRED, &bp)) != 0) {
107 		brelse(bp);
108 		return (error);
109 	}
110 	if (ap->a_res)
111 		*ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset);
112 	*ap->a_bpp = bp;
113 	return (0);
114 }
115 
116 #ifdef DIAGNOSTIC
117 void
118 ext2fs_checkoverlap(bp, ip)
119 	struct buf *bp;
120 	struct inode *ip;
121 {
122 #if 0
123 	struct buf *ebp, *ep;
124 	daddr_t start, last;
125 	struct vnode *vp;
126 
127 	ebp = &buf[nbuf];
128 	start = bp->b_blkno;
129 	last = start + btodb(bp->b_bcount) - 1;
130 	for (ep = buf; ep < ebp; ep++) {
131 		if (ep == bp || (ep->b_flags & B_INVAL) ||
132 			ep->b_vp == NULLVP)
133 			continue;
134 		if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL))
135 			continue;
136 		if (vp != ip->i_devvp)
137 			continue;
138 		/* look for overlap */
139 		if (ep->b_bcount == 0 || ep->b_blkno > last ||
140 			ep->b_blkno + btodb(ep->b_bcount) <= start)
141 			continue;
142 		vprint("Disk overlap", vp);
143 		printf("\tstart %" PRId64 ", end %" PRId64 " overlap start "
144 			"%" PRId64 ", end %" PRId64 "\n",
145 			start, last, ep->b_blkno,
146 			ep->b_blkno + btodb(ep->b_bcount) - 1);
147 		panic("Disk buffer overlap");
148 	}
149 #else
150 	printf("ext2fs_checkoverlap disabled due to buffer cache implementation changes\n");
151 #endif
152 }
153 #endif
154