xref: /csrg-svn/sys/ufs/lfs/lfs_inode.c (revision 54694)
1 /*
2  * Copyright (c) 1986, 1989, 1991 Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  *
7  *	@(#)lfs_inode.c	7.70 (Berkeley) 07/05/92
8  */
9 
10 #include <sys/param.h>
11 #include <sys/systm.h>
12 #include <sys/mount.h>
13 #include <sys/proc.h>
14 #include <sys/file.h>
15 #include <sys/buf.h>
16 #include <sys/vnode.h>
17 #include <sys/kernel.h>
18 #include <sys/malloc.h>
19 
20 #include <vm/vm.h>
21 
22 #include <ufs/ufs/quota.h>
23 #include <ufs/ufs/inode.h>
24 #include <ufs/ufs/ufsmount.h>
25 #include <ufs/ufs/ufs_extern.h>
26 
27 #include <ufs/lfs/lfs.h>
28 #include <ufs/lfs/lfs_extern.h>
29 
30 int
31 lfs_init()
32 {
33 #ifdef VERBOSE
34 	printf("lfs_init\n");
35 #endif
36 	return (ufs_init());
37 }
38 
39 /* Search a block for a specific dinode. */
40 struct dinode *
41 lfs_ifind(fs, ino, dip)
42 	struct lfs *fs;
43 	ino_t ino;
44 	register struct dinode *dip;
45 {
46 	register int cnt;
47 	register struct dinode *ldip;
48 
49 #ifdef VERBOSE
50 	printf("lfs_ifind: inode %d\n", ino);
51 #endif
52 	for (cnt = INOPB(fs), ldip = dip + (cnt - 1); cnt--; --ldip)
53 		if (ldip->di_inum == ino)
54 			return (ldip);
55 
56 	panic("lfs_ifind: dinode %u not found", ino);
57 	/* NOTREACHED */
58 }
59 
60 int
61 lfs_update(ap)
62 	struct vop_update_args /* {
63 		struct vnode *a_vp;
64 		struct timeval *a_ta;
65 		struct timeval *a_tm;
66 		int a_waitfor;
67 	} */ *ap;
68 {
69 	struct vnode *vp = ap->a_vp;
70 	struct inode *ip;
71 
72 #ifdef VERBOSE
73 	printf("lfs_update\n");
74 #endif
75 	if (vp->v_mount->mnt_flag & MNT_RDONLY)
76 		return (0);
77 	ip = VTOI(vp);
78 	if ((ip->i_flag & (IUPD|IACC|ICHG|IMOD)) == 0)
79 		return (0);
80 	if (ip->i_flag&IACC)
81 		ip->i_atime.ts_sec = ap->a_ta->tv_sec;
82 	if (ip->i_flag&IUPD) {
83 		ip->i_mtime.ts_sec = ap->a_tm->tv_sec;
84 		(ip)->i_modrev++;
85 	}
86 	if (ip->i_flag&ICHG)
87 		ip->i_ctime.ts_sec = time.tv_sec;
88 	ip->i_flag &= ~(IUPD|IACC|ICHG|IMOD);
89 
90 	/* Push back the vnode and any dirty blocks it may have. */
91 	return (ap->a_waitfor ? lfs_vflush(vp) : 0);
92 }
93 
94 /* Update segment usage information when removing a block. */
95 #define UPDATE_SEGUSE \
96 	if (lastseg != -1) { \
97 		LFS_SEGENTRY(sup, fs, lastseg, sup_bp); \
98 		sup->su_nbytes -= num << fs->lfs_bshift; \
99 		LFS_UBWRITE(sup_bp); \
100 		blocksreleased += num; \
101 	}
102 
103 #define SEGDEC { \
104 	if (daddr != UNASSIGNED) { \
105 		if (lastseg != (seg = datosn(fs, daddr))) { \
106 			UPDATE_SEGUSE; \
107 			num = 1; \
108 			lastseg = seg; \
109 		} else \
110 			++num; \
111 	} \
112 }
113 
114 /*
115  * Truncate the inode ip to at most length size.  Update segment usage
116  * table information.
117  */
118 /* ARGSUSED */
119 int
120 lfs_truncate(ap)
121 	struct vop_truncate_args /* {
122 		struct vnode *a_vp;
123 		off_t a_length;
124 		int a_flags;
125 		struct ucred *a_cred;
126 		struct proc *a_p;
127 	} */ *ap;
128 {
129 	register INDIR *inp;
130 	register int i;
131 	register daddr_t *daddrp;
132 	register struct vnode *vp = ap->a_vp;
133 	off_t length = ap->a_length;
134 	struct buf *bp, *sup_bp;
135 	struct ifile *ifp;
136 	struct inode *ip;
137 	struct lfs *fs;
138 	INDIR a[NIADDR + 2], a_end[NIADDR + 2];
139 	SEGUSE *sup;
140 	daddr_t daddr, lastblock, lbn, olastblock;
141 	long off, blocksreleased;
142 	int e1, e2, depth, lastseg, num, offset, seg, size;
143 
144 #ifdef VERBOSE
145 	printf("lfs_truncate\n");
146 #endif
147 	vnode_pager_setsize(vp, (u_long)length);
148 
149 	ip = VTOI(vp);
150 	fs = ip->i_lfs;
151 
152 	/* If truncating the file to 0, update the version number. */
153 	if (length == 0) {
154 		LFS_IENTRY(ifp, fs, ip->i_number, bp);
155 		++ifp->if_version;
156 		LFS_UBWRITE(bp);
157 	}
158 
159 	/* If length is larger than the file, just update the times. */
160 	if (ip->i_size <= length) {
161 		ip->i_flag |= ICHG|IUPD;
162 		return (VOP_UPDATE(vp, &time, &time, 1));
163 	}
164 
165 	/*
166 	 * Calculate index into inode's block list of last direct and indirect
167 	 * blocks (if any) which we want to keep.  Lastblock is 0 when the
168 	 * file is truncated to 0.
169 	 */
170 	lastblock = lblkno(fs, length + fs->lfs_bsize - 1);
171 	olastblock = lblkno(fs, ip->i_size + fs->lfs_bsize - 1) - 1;
172 
173 	/*
174 	 * Update the size of the file. If the file is not being truncated to
175 	 * a block boundry, the contents of the partial block following the end
176 	 * of the file must be zero'ed in case it ever become accessable again
177 	 * because of subsequent file growth.
178 	 */
179 	offset = blkoff(fs, length);
180 	if (offset == 0)
181 		ip->i_size = length;
182 	else {
183 		lbn = lblkno(fs, length);
184 #ifdef QUOTA
185 		if (e1 = getinoquota(ip))
186 			return (e1);
187 #endif
188 		if (e1 = bread(vp, lbn, fs->lfs_bsize, NOCRED, &bp))
189 			return (e1);
190 		ip->i_size = length;
191 		size = blksize(fs);
192 		(void)vnode_pager_uncache(vp);
193 		bzero(bp->b_un.b_addr + offset, (unsigned)(size - offset));
194 		allocbuf(bp, size);
195 		LFS_UBWRITE(bp);
196 	}
197 	/*
198 	 * Modify sup->su_nbyte counters for each deleted block; keep track
199 	 * of number of blocks removed for ip->i_blocks.
200 	 */
201 	blocksreleased = 0;
202 	num = 0;
203 	lastseg = -1;
204 
205 	for (lbn = olastblock; lbn >= lastblock;) {
206 		lfs_bmaparray(vp, lbn, &daddr, a, &depth);
207 		if (lbn == olastblock)
208 			for (i = NIADDR + 2; i--;)
209 				a_end[i] = a[i];
210 		switch (depth) {
211 		case 0:				/* Direct block. */
212 			daddr = ip->i_db[lbn];
213 			SEGDEC;
214 			ip->i_db[lbn] = 0;
215 			--lbn;
216 			break;
217 #ifdef DIAGNOSTIC
218 		case 1:				/* An indirect block. */
219 			panic("lfs_truncate: lfs_bmaparray returned depth 1");
220 			/* NOTREACHED */
221 #endif
222 		default:			/* Chain of indirect blocks. */
223 			inp = a + --depth;
224 			if (inp->in_off > 0 && lbn != lastblock) {
225 				lbn -= inp->in_off < lbn - lastblock ?
226 				    inp->in_off : lbn - lastblock;
227 				break;
228 			}
229 			for (; depth && (inp->in_off == 0 || lbn == lastblock);
230 			    --inp, --depth) {
231 				/*
232 				 * XXX
233 				 * The indirect block may not yet exist, so
234 				 * bread will create one just so we can free
235 				 * it.
236 				 */
237 				if (bread(vp,
238 				    inp->in_lbn, fs->lfs_bsize, NOCRED, &bp))
239 					panic("lfs_truncate: bread bno %d",
240 					    inp->in_lbn);
241 				daddrp = bp->b_un.b_daddr + inp->in_off;
242 				for (i = inp->in_off;
243 				    i++ <= a_end[depth].in_off;) {
244 					daddr = *daddrp++;
245 					SEGDEC;
246 				}
247 				a_end[depth].in_off = NINDIR(fs) - 1;
248 				if (inp->in_off == 0)
249 					brelse (bp);
250 				else {
251 					bzero(bp->b_un.b_daddr + inp->in_off,
252 					    fs->lfs_bsize -
253 					    inp->in_off * sizeof(daddr_t));
254 					LFS_UBWRITE(bp);
255 				}
256 			}
257 			if (depth == 0 && a[1].in_off == 0) {
258 				off = a[0].in_off;
259 				daddr = ip->i_ib[off];
260 				SEGDEC;
261 				ip->i_ib[off] = 0;
262 			}
263 			if (lbn == lastblock || lbn <= NDADDR)
264 				--lbn;
265 			else {
266 				lbn -= NINDIR(fs);
267 				if (lbn < lastblock)
268 					lbn = lastblock;
269 			}
270 		}
271 	}
272 	UPDATE_SEGUSE;
273 	ip->i_blocks -= blocksreleased;
274 	/*
275 	 * XXX
276 	 * Currently, we don't know when we allocate an indirect block, so
277 	 * ip->i_blocks isn't getting incremented appropriately.  As a result,
278 	 * when we delete any indirect blocks, we get a bad number here.
279 	 */
280 	if (ip->i_blocks < 0)
281 		ip->i_blocks = 0;
282 	ip->i_flag |= ICHG|IUPD;
283 	e1 = vinvalbuf(vp, length > 0, ap->a_cred, ap->a_p);
284 	e2 = VOP_UPDATE(vp, &time, &time, MNT_WAIT);
285 	return (e1 ? e1 : e2 ? e2 : 0);
286 }
287