lfs_inode.c revision 1.4 
1/*      $NetBSD: lfs_inode.c,v 1.4 2001/11/02 05:44:46 lukem Exp $ */
2
3/*-
4 * Copyright (c) 1980, 1991, 1993, 1994
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. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *      This product includes software developed by the University of
18 *      California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#include <sys/cdefs.h>
37#ifndef lint
38__COPYRIGHT("@(#) Copyright (c) 1980, 1991, 1993, 1994\n\
39        The Regents of the University of California.  All rights reserved.\n");
40#endif /* not lint */
41
42#ifndef lint
43#if 0
44static char sccsid[] = "@(#)main.c      8.6 (Berkeley) 5/1/95";
45#else
46__RCSID("$NetBSD: lfs_inode.c,v 1.4 2001/11/02 05:44:46 lukem Exp $");
47#endif
48#endif /* not lint */
49
50#include <sys/param.h>
51#include <sys/time.h>
52#include <sys/stat.h>
53#include <ufs/ufs/dir.h>
54#include <ufs/ufs/dinode.h>
55#include <sys/mount.h>
56#include <ufs/lfs/lfs.h>
57
58#include <protocols/dumprestore.h>
59
60#include <ctype.h>
61#include <errno.h>
62#include <fts.h>
63#include <stdio.h>
64#ifdef __STDC__
65#include <string.h>
66#include <unistd.h>
67#endif
68
69#include "dump.h"
70
71#define MAXIFPB        (MAXBSIZE / sizeof(IFILE))
72
73#define	HASDUMPEDFILE	0x1
74#define	HASSUBDIRS	0x2
75
76struct lfs *sblock;
77
78/*
79 * Read the superblock from disk, and check its magic number.
80 * Determine whether byte-swapping needs to be done on this filesystem.
81 */
82int
83fs_read_sblock(char *superblock)
84{
85	char tbuf[LFS_SBPAD];
86	int ns = 0;
87	off_t sboff = LFS_LABELPAD;
88
89	sblock = (struct lfs *)superblock;
90	while(1) {
91		rawread(sboff, (char *) sblock, LFS_SBPAD);
92		if (sblock->lfs_magic != LFS_MAGIC) {
93#ifdef notyet
94			if (sblock->lfs_magic == bswap32(LFS_MAGIC)) {
95				lfs_sb_swap(sblock, sblock, 0);
96				ns = 1;
97			} else
98#endif
99				quit("bad sblock magic number\n");
100		}
101		if (fsbtob(sblock, sblock->lfs_sboffs[0]) != sboff) {
102			sboff = fsbtob(sblock, sblock->lfs_sboffs[0]);
103			continue;
104		}
105		break;
106	}
107
108	/*
109	 * Read the secondary and take the older of the two
110	 */
111	rawread(fsbtob(sblock, sblock->lfs_sboffs[1]), tbuf, LFS_SBPAD);
112#ifdef notyet
113	if (ns)
114		lfs_sb_swap(tbuf, tbuf, 0);
115#endif
116	if (((struct lfs *)tbuf)->lfs_magic != LFS_MAGIC) {
117		msg("Warning: secondary superblock at 0x%x bad magic\n",
118			fsbtodb(sblock, sblock->lfs_sboffs[1]));
119	} else {
120		if (sblock->lfs_version > 1) {
121			if (((struct lfs *)tbuf)->lfs_serial < sblock->lfs_serial) {
122				memcpy(sblock, tbuf, LFS_SBPAD);
123				sboff = fsbtob(sblock, sblock->lfs_sboffs[1]);
124			}
125		} else {
126			if (((struct lfs *)tbuf)->lfs_otstamp < sblock->lfs_otstamp) {
127				memcpy(sblock, tbuf, LFS_SBPAD);
128				sboff = fsbtob(sblock, sblock->lfs_sboffs[1]);
129			}
130		}
131	}
132	if (sboff != LFS_SBPAD) {
133		msg("Using superblock at alternate location 0x%lx\n",
134		    (unsigned long)(btodb(sboff)));
135	}
136
137	return ns;
138}
139
140/*
141 * Fill in the ufsi struct, as well as the maxino and dev_bsize global
142 * variables.
143 */
144struct ufsi *
145fs_parametrize(void)
146{
147	static struct ufsi ufsi;
148
149	spcl.c_flags = iswap32(iswap32(spcl.c_flags) | DR_NEWINODEFMT);
150
151	ufsi.ufs_dsize = fsbtodb(sblock,sblock->lfs_size);
152	if (sblock->lfs_version == 1)
153		ufsi.ufs_dsize = sblock->lfs_size >> sblock->lfs_blktodb;
154	ufsi.ufs_bsize = sblock->lfs_bsize;
155	ufsi.ufs_bshift = sblock->lfs_bshift;
156	ufsi.ufs_fsize = sblock->lfs_fsize;
157	ufsi.ufs_frag = sblock->lfs_frag;
158	ufsi.ufs_fsatoda = sblock->lfs_fsbtodb;
159	if (sblock->lfs_version == 1)
160		ufsi.ufs_fsatoda = 0;
161	ufsi.ufs_nindir = sblock->lfs_nindir;
162	ufsi.ufs_inopb = sblock->lfs_inopb;
163	ufsi.ufs_maxsymlinklen = sblock->lfs_maxsymlinklen;
164	ufsi.ufs_bmask = ~(sblock->lfs_bmask);
165	ufsi.ufs_qbmask = sblock->lfs_bmask;
166	ufsi.ufs_fmask = ~(sblock->lfs_ffmask);
167	ufsi.ufs_qfmask = sblock->lfs_ffmask;
168
169	dev_bsize = sblock->lfs_bsize >> sblock->lfs_blktodb;
170
171	return &ufsi;
172}
173
174ino_t
175fs_maxino(void)
176{
177	return ((getino(sblock->lfs_ifile)->di_size
178		   - (sblock->lfs_cleansz + sblock->lfs_segtabsz)
179		   * sblock->lfs_bsize)
180		  / sblock->lfs_bsize) * sblock->lfs_ifpb - 1;
181}
182
183/*
184 * XXX KS - I know there's a better way to do this.
185 */
186#define BASE_SINDIR (NDADDR)
187#define BASE_DINDIR (NDADDR+NINDIR(fs))
188#define BASE_TINDIR (NDADDR+NINDIR(fs)+NINDIR(fs)*NINDIR(fs))
189
190#define D_UNITS (NINDIR(fs))
191#define T_UNITS (NINDIR(fs)*NINDIR(fs))
192
193static daddr_t
194lfs_bmap(struct lfs *fs, struct dinode *idinode, ufs_daddr_t lbn)
195{
196	ufs_daddr_t residue, up;
197	int off=0;
198	char bp[MAXBSIZE];
199
200	if(lbn > 0 && lbn > lblkno(fs, idinode->di_size)) {
201		return UNASSIGNED;
202	}
203	/*
204	 * Indirect blocks: if it is a first-level indirect, pull its
205	 * address from the inode; otherwise, call ourselves to find the
206	 * address of the parent indirect block, and load that to find
207	 * the desired address.
208	 */
209	if(lbn < 0) {
210		lbn *= -1;
211		if(lbn == NDADDR) {
212			/* printf("lbn %d: single indir base\n", -lbn); */
213			return idinode->di_ib[0]; /* single indirect */
214		} else if(lbn == BASE_DINDIR+1) {
215			/* printf("lbn %d: double indir base\n", -lbn); */
216			return idinode->di_ib[1]; /* double indirect */
217		} else if(lbn == BASE_TINDIR+2) {
218			/* printf("lbn %d: triple indir base\n", -lbn); */
219			return idinode->di_ib[2]; /* triple indirect */
220		}
221
222		/*
223		 * Find the immediate parent. This is essentially finding the
224		 * residue of modulus, and then rounding accordingly.
225		 */
226		residue = (lbn-NDADDR) % NINDIR(fs);
227		if(residue == 1) {
228			/* Double indirect.  Parent is the triple. */
229			up = idinode->di_ib[2];
230			off = (lbn-2-BASE_TINDIR)/(NINDIR(fs)*NINDIR(fs));
231			if(up == UNASSIGNED || up == LFS_UNUSED_DADDR)
232				return UNASSIGNED;
233			/* printf("lbn %d: parent is the triple\n", -lbn); */
234			bread(fsbtodb(sblock, up), bp, sblock->lfs_bsize);
235			return ((daddr_t *)bp)[off];
236		} else /* residue == 0 */ {
237			/* Single indirect.  Two cases. */
238			if(lbn < BASE_TINDIR) {
239				/* Parent is the double, simple */
240				up = -(BASE_DINDIR) - 1;
241				off = (lbn-BASE_DINDIR) / D_UNITS;
242				/* printf("lbn %d: parent is %d/%d\n", -lbn, up,off); */
243			} else {
244				/* Ancestor is the triple, more complex */
245				up = ((lbn-BASE_TINDIR) / T_UNITS)
246					* T_UNITS + BASE_TINDIR + 1;
247				off = (lbn/D_UNITS) - (up/D_UNITS);
248				up = -up;
249				/* printf("lbn %d: parent is %d/%d\n", -lbn, up,off); */
250			}
251		}
252	} else {
253		/* Direct block.  Its parent must be a single indirect. */
254		if(lbn < NDADDR)
255			return idinode->di_db[lbn];
256		else {
257			/* Parent is an indirect block. */
258			up = -(((lbn-NDADDR) / D_UNITS) * D_UNITS + NDADDR);
259			off = (lbn-NDADDR) % D_UNITS;
260			/* printf("lbn %d: parent is %d/%d\n", lbn,up,off); */
261		}
262	}
263	up = lfs_bmap(fs,idinode,up);
264	if(up == UNASSIGNED || up == LFS_UNUSED_DADDR)
265		return UNASSIGNED;
266	bread(fsbtodb(sblock, up), bp, sblock->lfs_bsize);
267	return ((daddr_t *)bp)[off];
268}
269
270static struct ifile *
271lfs_ientry(ino_t ino)
272{
273    static struct ifile ifileblock[MAXIFPB];
274    static daddr_t ifblkno;
275    ufs_daddr_t lbn;
276    daddr_t blkno;
277
278    lbn = ino/sblock->lfs_ifpb + sblock->lfs_cleansz + sblock->lfs_segtabsz;
279    blkno = lfs_bmap(sblock,getino(sblock->lfs_ifile),lbn);
280    if(blkno != ifblkno)
281	    bread(fsbtodb(sblock, blkno), (char *)ifileblock,
282		  sblock->lfs_bsize);
283    return ifileblock + (ino%sblock->lfs_ifpb);
284}
285
286/* Search a block for a specific dinode. */
287static struct dinode *
288lfs_ifind(struct lfs *fs, ino_t ino, struct dinode *dip)
289{
290	register int cnt;
291
292	for(cnt=0;cnt<INOPB(fs);cnt++)
293		if(dip[cnt].di_inumber == ino)
294			return &(dip[cnt]);
295	return NULL;
296}
297
298struct dinode *
299getino(inum)
300	ino_t inum;
301{
302	static daddr_t inoblkno;
303	daddr_t blkno;
304	static struct dinode inoblock[MAXINOPB];
305	static struct dinode ifile_dinode; /* XXX fill this in */
306	static struct dinode empty_dinode; /* Always stays zeroed */
307	struct dinode *dp;
308
309	if(inum == sblock->lfs_ifile) {
310		/* Load the ifile inode if not already */
311		if(ifile_dinode.di_u.inumber == 0) {
312			blkno = sblock->lfs_idaddr;
313			bread(fsbtodb(sblock, blkno), (char *)inoblock,
314				(int)sblock->lfs_bsize);
315			dp = lfs_ifind(sblock, inum, inoblock);
316			ifile_dinode = *dp; /* Structure copy */
317		}
318		return &ifile_dinode;
319	}
320
321	curino = inum;
322	blkno = lfs_ientry(inum)->if_daddr;
323	if(blkno == LFS_UNUSED_DADDR)
324		return &empty_dinode;
325
326	if(blkno != inoblkno) {
327		bread(fsbtodb(sblock, blkno), (char *)inoblock,
328			(int)sblock->lfs_bsize);
329#ifdef notyet
330		if (needswap)
331			for (i = 0; i < MAXINOPB; i++)
332				ffs_dinode_swap(&inoblock[i], &inoblock[i]);
333#endif
334	}
335	return lfs_ifind(sblock, inum, inoblock);
336}
337