xref: /original-bsd/sys/ufs/lfs/lfs_inode.c (revision fd3027f5)
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	7.74 (Berkeley) 07/22/92
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_SYNC ? 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 timeval tv;
136 	struct ifile *ifp;
137 	struct inode *ip;
138 	struct lfs *fs;
139 	INDIR a[NIADDR + 2], a_end[NIADDR + 2];
140 	SEGUSE *sup;
141 	daddr_t daddr, lastblock, lbn, olastblock;
142 	long off, blocksreleased;
143 	int e1, e2, depth, lastseg, num, offset, seg, size;
144 
145 #ifdef VERBOSE
146 	printf("lfs_truncate\n");
147 #endif
148 	ip = VTOI(vp);
149 	tv = time;
150 	if (vp->v_type == VLNK && vp->v_mount->mnt_maxsymlinklen > 0) {
151 #ifdef DIAGNOSTIC
152 		if (length != 0)
153 			panic("lfs_truncate: partial truncate of symlink");
154 #endif
155 		bzero((char *)&ip->i_shortlink, (u_int)ip->i_size);
156 		ip->i_size = 0;
157 		ip->i_flag |= ICHG|IUPD;
158 		return (VOP_UPDATE(vp, &tv, &tv, 0));
159 	}
160 	vnode_pager_setsize(vp, (u_long)length);
161 
162 	fs = ip->i_lfs;
163 
164 	/* If truncating the file to 0, update the version number. */
165 	if (length == 0) {
166 		LFS_IENTRY(ifp, fs, ip->i_number, bp);
167 		++ifp->if_version;
168 		LFS_UBWRITE(bp);
169 	}
170 
171 	/* If length is larger than the file, just update the times. */
172 	if (ip->i_size <= length) {
173 		ip->i_flag |= ICHG|IUPD;
174 		return (VOP_UPDATE(vp, &tv, &tv, 0));
175 	}
176 
177 	/*
178 	 * Calculate index into inode's block list of last direct and indirect
179 	 * blocks (if any) which we want to keep.  Lastblock is 0 when the
180 	 * file is truncated to 0.
181 	 */
182 	lastblock = lblkno(fs, length + fs->lfs_bsize - 1);
183 	olastblock = lblkno(fs, ip->i_size + fs->lfs_bsize - 1) - 1;
184 
185 	/*
186 	 * Update the size of the file. If the file is not being truncated to
187 	 * a block boundry, the contents of the partial block following the end
188 	 * of the file must be zero'ed in case it ever become accessable again
189 	 * because of subsequent file growth.
190 	 */
191 	offset = blkoff(fs, length);
192 	if (offset == 0)
193 		ip->i_size = length;
194 	else {
195 		lbn = lblkno(fs, length);
196 #ifdef QUOTA
197 		if (e1 = getinoquota(ip))
198 			return (e1);
199 #endif
200 		if (e1 = bread(vp, lbn, fs->lfs_bsize, NOCRED, &bp))
201 			return (e1);
202 		ip->i_size = length;
203 		size = blksize(fs);
204 		(void)vnode_pager_uncache(vp);
205 		bzero(bp->b_un.b_addr + offset, (unsigned)(size - offset));
206 		allocbuf(bp, size);
207 		LFS_UBWRITE(bp);
208 	}
209 	/*
210 	 * Modify sup->su_nbyte counters for each deleted block; keep track
211 	 * of number of blocks removed for ip->i_blocks.
212 	 */
213 	blocksreleased = 0;
214 	num = 0;
215 	lastseg = -1;
216 
217 	for (lbn = olastblock; lbn >= lastblock;) {
218 		lfs_bmaparray(vp, lbn, &daddr, a, &depth);
219 		if (lbn == olastblock)
220 			for (i = NIADDR + 2; i--;)
221 				a_end[i] = a[i];
222 		switch (depth) {
223 		case 0:				/* Direct block. */
224 			daddr = ip->i_db[lbn];
225 			SEGDEC;
226 			ip->i_db[lbn] = 0;
227 			--lbn;
228 			break;
229 #ifdef DIAGNOSTIC
230 		case 1:				/* An indirect block. */
231 			panic("lfs_truncate: lfs_bmaparray returned depth 1");
232 			/* NOTREACHED */
233 #endif
234 		default:			/* Chain of indirect blocks. */
235 			inp = a + --depth;
236 			if (inp->in_off > 0 && lbn != lastblock) {
237 				lbn -= inp->in_off < lbn - lastblock ?
238 				    inp->in_off : lbn - lastblock;
239 				break;
240 			}
241 			for (; depth && (inp->in_off == 0 || lbn == lastblock);
242 			    --inp, --depth) {
243 				/*
244 				 * XXX
245 				 * The indirect block may not yet exist, so
246 				 * bread will create one just so we can free
247 				 * it.
248 				 */
249 				if (bread(vp,
250 				    inp->in_lbn, fs->lfs_bsize, NOCRED, &bp))
251 					panic("lfs_truncate: bread bno %d",
252 					    inp->in_lbn);
253 				daddrp = bp->b_un.b_daddr + inp->in_off;
254 				for (i = inp->in_off;
255 				    i++ <= a_end[depth].in_off;) {
256 					daddr = *daddrp++;
257 					SEGDEC;
258 				}
259 				a_end[depth].in_off = NINDIR(fs) - 1;
260 				if (inp->in_off == 0)
261 					brelse (bp);
262 				else {
263 					bzero(bp->b_un.b_daddr + inp->in_off,
264 					    fs->lfs_bsize -
265 					    inp->in_off * sizeof(daddr_t));
266 					LFS_UBWRITE(bp);
267 				}
268 			}
269 			if (depth == 0 && a[1].in_off == 0) {
270 				off = a[0].in_off;
271 				daddr = ip->i_ib[off];
272 				SEGDEC;
273 				ip->i_ib[off] = 0;
274 			}
275 			if (lbn == lastblock || lbn <= NDADDR)
276 				--lbn;
277 			else {
278 				lbn -= NINDIR(fs);
279 				if (lbn < lastblock)
280 					lbn = lastblock;
281 			}
282 		}
283 	}
284 	UPDATE_SEGUSE;
285 	ip->i_blocks -= btodb(blocksreleased << fs->lfs_bshift);
286 #ifdef DIAGNOSTIC
287 	if (ip->i_blocks < 0)
288 		panic("lfs_truncate: block count < 0");
289 #endif
290 	ip->i_flag |= ICHG|IUPD;
291 	e1 = vinvalbuf(vp, length > 0, ap->a_cred, ap->a_p);
292 	e2 = VOP_UPDATE(vp, &tv, &tv, 0);
293 	return (e1 ? e1 : e2 ? e2 : 0);
294 }
295