xref: /openbsd/sys/ufs/ext2fs/ext2fs_subr.c (revision cca36db2)
1 /*	$OpenBSD: ext2fs_subr.c,v 1.27 2011/07/04 20:35:35 deraadt Exp $	*/
2 /*	$NetBSD: ext2fs_subr.c,v 1.1 1997/06/11 09:34:03 bouyer Exp $	*/
3 
4 /*
5  * Copyright (c) 1997 Manuel Bouyer.
6  * Copyright (c) 1982, 1986, 1989, 1993
7  *	The Regents of the University of California.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)ffs_subr.c	8.2 (Berkeley) 9/21/93
34  * Modified for ext2fs by Manuel Bouyer.
35  */
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/vnode.h>
40 #include <sys/mount.h>
41 #include <sys/buf.h>
42 #include <sys/specdev.h>
43 
44 #include <ufs/ufs/quota.h>
45 #include <ufs/ufs/inode.h>
46 #include <ufs/ufs/ufsmount.h>
47 
48 #include <ufs/ext2fs/ext2fs.h>
49 #include <ufs/ext2fs/ext2fs_extern.h>
50 
51 #include <miscfs/fifofs/fifo.h>
52 
53 union _qcvt {
54 	int64_t qcvt;
55 	int32_t val[2];
56 };
57 
58 #define SETHIGH(q, h) {			\
59 	union _qcvt tmp;		\
60 	tmp.qcvt = (q);			\
61 	tmp.val[_QUAD_HIGHWORD] = (h);	\
62 	(q) = tmp.qcvt;			\
63 }
64 
65 #define SETLOW(q, l) {			\
66 	union _qcvt tmp;		\
67 	tmp.qcvt = (q);			\
68 	tmp.val[_QUAD_LOWWORD] = (l);	\
69 	(q) = tmp.qcvt;			\
70 }
71 
72 #ifdef _KERNEL
73 
74 /*
75  * Return buffer with the contents of block "offset" from the beginning of
76  * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
77  * remaining space in the directory.
78  */
79 int
80 ext2fs_bufatoff(struct inode *ip, off_t offset, char **res, struct buf **bpp)
81 {
82 	struct vnode *vp;
83 	struct m_ext2fs *fs;
84 	struct buf *bp;
85 	int32_t lbn;
86 	int error;
87 
88 	vp = ITOV(ip);
89 	fs = ip->i_e2fs;
90 	lbn = lblkno(fs, offset);
91 
92 	*bpp = NULL;
93 	if ((error = bread(vp, lbn, fs->e2fs_bsize, &bp)) != 0) {
94 		brelse(bp);
95 		return (error);
96 	}
97 	if (res)
98 		*res = (char *)bp->b_data + blkoff(fs, offset);
99 	*bpp = bp;
100 	return (0);
101 }
102 #endif
103 
104 #if defined(_KERNEL) && defined(DIAGNOSTIC)
105 void
106 ext2fs_checkoverlap(struct buf *bp, struct inode *ip)
107 {
108 	struct buf *ep;
109 	struct vnode *vp;
110 	daddr64_t start, last;
111 
112 	start = bp->b_blkno;
113 	last = start + btodb(bp->b_bcount) - 1;
114 	LIST_FOREACH(ep, &bufhead, b_list) {
115 		if (ep == bp || (ep->b_flags & B_INVAL) ||
116 			ep->b_vp == NULLVP)
117 			continue;
118 		if (VOP_BMAP(ep->b_vp, (daddr64_t)0, &vp, NULL, NULL))
119 			continue;
120 		if (vp != ip->i_devvp)
121 			continue;
122 		/* look for overlap */
123 		if (ep->b_bcount == 0 || ep->b_blkno > last ||
124 			ep->b_blkno + btodb(ep->b_bcount) <= start)
125 			continue;
126 		vprint("Disk overlap", vp);
127 		printf("\tstart %lld, end %lld overlap start %lld, end %lld\n",
128 			start, last, ep->b_blkno,
129 			ep->b_blkno + btodb(ep->b_bcount) - 1);
130 		panic("Disk buffer overlap");
131 	}
132 }
133 #endif /* DIAGNOSTIC */
134 
135 /*
136  * Initialize the vnode associated with a new inode, handle aliased vnodes.
137  */
138 int
139 ext2fs_vinit(struct mount *mp, struct vops *specops,
140     struct vops *fifoops, struct vnode **vpp)
141 {
142 	struct inode *ip;
143 	struct vnode *vp, *nvp;
144 	struct timeval tv;
145 
146 	vp = *vpp;
147 	ip = VTOI(vp);
148 	vp->v_type = IFTOVT(ip->i_e2fs_mode);
149 
150 	switch(vp->v_type) {
151 	case VCHR:
152 	case VBLK:
153 		vp->v_op = specops;
154 
155 		nvp = checkalias(vp, fs2h32(ip->i_e2din->e2di_rdev), mp);
156 		if (nvp != NULL) {
157 			/*
158 			 * Discard unneeded vnode, but save its inode. Note
159 			 * that the lock is carried over in the inode to the
160 			 * replacement vnode.
161 			 */
162 			nvp->v_data = vp->v_data;
163 			vp->v_data = NULL;
164 			vp->v_op = &spec_vops;
165 #ifdef VFSLCKDEBUG
166 			vp->v_flag &= ~VLOCKSWORK;
167 #endif
168 			vrele(vp);
169 			vgone(vp);
170 			/* Reinitialize aliased vnode. */
171 			vp = nvp;
172 			ip->i_vnode = vp;
173 		}
174 
175 		break;
176 
177 	case VFIFO:
178 #ifdef FIFO
179 		vp->v_op = fifoops;
180 		break;
181 #else
182 		return (EOPNOTSUPP);
183 #endif /* FIFO */
184 
185 	default:
186 
187 		break;
188 	}
189 
190 	if (ip->i_number == EXT2_ROOTINO)
191 		vp->v_flag |= VROOT;
192 
193 	/* Initialize modrev times */
194 	getmicrouptime(&tv);
195 	SETHIGH(ip->i_modrev, tv.tv_sec);
196 	SETLOW(ip->i_modrev, tv.tv_usec * 4294);
197 
198 	*vpp = vp;
199 
200 	return (0);
201 }
202